MFC r331475: loader consoles: Implement SGR 24, 25

Mostly for completeness sake- implement 24 (no underline) and 25 (no blink)

MFC r331416, r331440: Loader consoles: Implement SGR 22, reste intensity

r331416:
Loader consoles: Implement SGR 22, reset intensity

r331440:
Match broken style of vidconsole.c

This particular function uses a broken mix of indentation styles. Match it
for the newly added SGR 22 bits.

MFC r325834,r325997,326502: Move sys/boot to stand/

This is effectively a direct commit to stable/11, due to differences between
stable/11 and head. Changes to DTS in sys/boot/fdt/dts were often
accompanied by kernel changes. Many of these were also risc-v updates that
likely had many more dependencies to MFC.

Because of this, sys/boot/fdt/dts remains as-is while everything else in
sys/boot relocates to stand/.

r325834: Move sys/boot to stand. Fix all references to new location

r325997: Remove empty directories.

r326502: Document the sys/boot -> stand move in hier.7 and the top-level README.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix a long standing bug. The caller expects a non-zero value for success.
Luckily keyboard probing was turned off by default from the first revision.

Submitted by: Alexander Sack (asack at niksun dot com)
MFC after: 3 days

Consolidate duplicate definitions of V86_CY() and V86_ZR() which check for
the carry and zero flags being set, respectively, in <btxv86.h> and use
them throughout the x86 boot code.

Add new loader console type: "spinconsole". This console selects the
video console which doesn't take any input from keyboard and hides
all output replacing it with ``spinning'' character (useful for
embedded products and custom installations).

Sponsored by: Sippy Software, Inc.

Fix 'implicit int' instance.

Use __FBSDID().
Also some minor copyright style cleanups.

Fix the ANSI color escape sequence \E[m.

- Corretly map the ansi color number to a PC BIOS color.
- Handle multiple arguments to the escape sequence.

Fix the local macro: isvisible().

- The space char (0x20) IS a visible char :-)

Fix the function CD(): "Clear to the end of the screen".

- When the video BIOS is called to clear the region (x, y)-(79, 24)
(by scrolling), the slashed region in Fig.1 is cleared. CD() is
supposed to clear the region shown in Fig.2.
x x
+-------+ +-------+
| | | |
y| ////| y| ////|
| ////| |///////|
| ////| |///////|
+-------+ +-------+
Fig.1 Fig.2

- Don't move the cursor during this operation.

This is white-space only change. No functional difference.

- Be consistent about placing spaces around keywords and
operators; don't mix statements like "if(A==B)" and "if (X == Y)",
"return(0)" and "return (-1)", "P=10" and "Q = 0", etc.

- Consitently indent lines. It's not good to indent by 8 columns
in one part of the file, and by 4 columns in the other part.

s/adress/address/

Inspired by: OpenBSD
MFC After: 1 week

Cleanup warnings. Most of these are signed/unsigned warnings, as well as
some added const's.

$Id$ -> $FreeBSD$

Fix a potential sign extension bug on 8-bit chars.
Outputting a backspace isn't supposed to be destructive.. It isn't on
most terminals, nor on the standard bios output (vs. TERM_EMU mode)

Add back ability to make beeps when using new TERM_EMU.

Submitted by: W Gerald Hicks <wghicks@bellsouth.net>

Add simple terminal emulator, compatible with cons25. Currently supported
capabilities are: AF, AB, cm, ho, me, cd. The code is hidden behind
-DTERM_EMU - should it cause any problems, you can remove this define
to get back the old behaviour.

You'll find some examples how to use it in src/share/examples/bootforth.

Reviewed by: jkh

- Add a new command 'lsdev' to list devices which might be likely to host
filesystems.
- New 'help' command and data in the help.* files (not yet installed),
provides topic and subtopic help, indexes, etc.
- Don't crash if the user tries to set an invalid console. Be helpful
instead.
- Expand tabs (badly) on the i386 video console.
- Some minor cosmetic changes.

Simplify the "is a character ready" test, so that we don't return a false
negative for keypresses with zero ascii values. This is in line with the
comconsole test, rather than being more ambitious.

Submitted by: rnordier

Only call vidc_init() once (unless forced).
Cosmetic change to the init-time character eater (like, make it increment
the index counter - if there's a problem, it would sit there in an infinite
loop instead of only running 10 times).

Request the flags back when checking for keyboard status.
Submitted by: rnordier

- Drain the keyboard buffer when initialising.
- Be pedantic about the return from int 16 fn 01.

aout_freebsd.c
Use bd_getdev() to work out a dev_t for the root device.
Allow $rootdev to override $currdev as the root device.

biosdisk.c
Save the slice table and disklabel when opening a disk.
Add bd_getdev(), which attempts to return a dev_t corresponding
to a given device. Cases which it still doesn't get right:
- The inevitable da-when-wd-also-exists
- Disks with no slice table (the slice number is not set correctly)
The first is difficult to get right, the second will be
fixed in an upcoming commit.

comconsole.c
vidconsole.c
getchar() should return an 8-bit value; some BIOSsen pack extra
information in %eax.

libi386.h
Remove some stale prototypes, add new ones.

Initial integration of the i386 bootloader and BTX.

- Discard large amounts of BIOS-related code in favour of the more compact
BTX vm86 interface.
- Build the loader module as ELF, although the resulting object is a.out,
make gensetdefs 32/64-bit sensitive and use a single copy of it.
- Throw away installboot, as it's no longer required.
- Use direct bcopy operations in the i386_copy module, as BTX
maps the first 16M of memory. Check operations against the
detected size of actual memory.

This commit was generated by cvs2svn to compensate for changes in r38465,
which included commits to RCS files with non-trunk default branches.

This is the new unified bootstrap, sometimes known previously as the
'three-stage' bootstrap.
There are a number of caveats with the code in its current state:
- The i386 bootstrap only supports booting from a floppy.
- The kernel and kld do not yet know how to deal with the extended
information and module summary passed in.
- PnP-based autodetection and demand loading of modules is not implemented.
- i386 ELF kernel loading is not ready yet.
- The i386 bootstrap is loaded via an ugly blockmap.

On the alpha, both net- and disk-booting (SRM console machines only) is
supported. No blockmaps are used by this code.

Obtained from: Parts from the NetBSD/i386 standalone bootstrap.