[debuglog] Migrate to zx_debuglog_create

Test: cq

Change-Id: Ia7aa2efefd0c1ac0ce3460159a9405d6f0b1777e

[logging] Migrate zircon off zx_log_read and zx_log_write

zx_log_create is trickier. It's essentially a version of
zx_debuglog_create that allows not passing a root resource.

ZX-2184

Change-Id: Ida3d6bacce2c4601a4c6a00fd0cf13c902eb1d41

[debug] Fix compiler nits so we can build with -Og

All changes were related to uninitialized variables accesses
that are optimized out in other builds.

Change-Id: Ide3d49fb7dcbf8211fa7a3624b7119e837c62019

[zx] Magenta -> Zircon

The Great Renaming is here!

Change-Id: I3229bdeb2a3d0e40fb4db6fec8ca7d971fbffb94

[debuglog][mxio][devhost] tidy up log flags, introduce local

- remove old subsystem identity flag values
(subsystems will return later in a better way)
- pull standard log flag definitions into syscalls/log.h
- introduce new LOCAL flag
- introduce DDK_LOG_L* variants
- pass flags through dprintf() to log write
- only filter on level flags

Change-Id: Ibeba1b27e9cfc543b441965414f2651ddfc749aa

[dlog] add some filter and display options

-p <pid> filters to only show messages from pid
-t shows only the text of the log messages, no metadata
-h show help

Change-Id: I23f598e27941fb215361bc8043557b4808771aed

[uapp][status] Use the new MX_OK and MX_ERR_* mx_status_t names

Change-Id: Iaa8c8c12736e49d202c33612b22d2acd528fcf2d

[system][uapp][dlog] remove unnecessary strlen

The buffer size was also modified as max string has a length of 28.

Change-Id: Ic1fb6ee0deb850bda15d80b6c9dd268a2e8880e8

[syscalls][log] log objects now use signals instead of blocking reads

Change-Id: I5a2c9f2a69966d386d164b568ebb433e6d846894

[syscalls][debuglog] mx_log_create() returns mx_status_t

Necessary work for the uint-ification of mx_handle_t.

Change-Id: I60ab858879d20314b19115e368a5d6ed76278ca1

[magenta][syscalls][headers] tidy up syscall structure related headers

For more complex syscalls, there are now sub-headers that declare their
structures and constants which must be included. This avoids pulling
a bunch of stuff into the global namespace whenever anyone needs to make
a syscall and includes magenta/syscalls.h

The magenta/syscalls-types.h no longer exists.

- magenta/syscalls/debug.h for debugger api defines
- magenta/syscalls/exception.h for exception defines
- magenta/syscalls/port.h for mx_port_*()
- magenta/syscalls/log.h for mx_log_*()
- magenta/syscalls/object.h for object info/property defines
- magenta/syscalls/pci.h for mx_pci_*() (ddk use only)

Change-Id: I636c28e4a9a08836d9543b539f236e9d38ecc11b

[system] align license and license banners with Fuchsia

This adjusts the Magenta userspace code to match the prevailing
license in Fuchsia (three-clause BSD), using the same banner
and license text.

Change-Id: I6b6d79435c5dbaa32027888874849e4f47aaa7be

[uapp][dlog] don't print extra newlines

Change-Id: I7a81de25a34ae61d6aa3ec77c974c81cc4c639b4

[dlog] fix dlog too pass the flag needed for readable log objects

Change-Id: I8eefa36d9bf908198b9848df33903a9c933339f9

[magenta][syscalls] move "private" syscalls to libddk

At some point these will be handle based and not possible for
arbitrary processes without the correct privilege (via handle)
to call, but until then at least make it a bit harder to use
them (need to include syscalls-ddk.h and link against libddk)
to discourage general use.

Change-Id: I8bb803f6d330aa0ee3e39d27068e5f893b1be99c

[syscalls][api] rename _magenta_*() to mx_*()

The _magenta_ prefix is pretty unwieldy.
This change simplifies that a bit.

This was done mechanically, and boots, runs, and passes tests
on qemu arm64, amd64, and NUC.

Change-Id: I8eb07db6ed6f4b8cac96344cc4ad65ce3f85f917

[system] clang-format all of userspace

Change-Id: I6bb6a9187a4af83ca5c0656f05d89aa3a09fa5fa

[magenta] Initial commit