sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

powerpc: clean up empty lines in .c and .h files

powerpc: Fix regression introduced in r342771

In r342771, I introduced a regression in Power by abusing the platform
smp_topo() method as a shortcut for providing the MI information needed for
the stated sysctls. The smp_topo() method was already called later by
sched_ule (under the name cpu_topo()), and initializes a static array of
scheduler topology information. I had skimmed the smp_topo_foo() functions
and assumed they were idempotent; empirically, they are not (or at least,
detect re-initialization and panic).

Do the cleaner thing I should have done in the first place and add a
platform method specifically for core- and thread-count probing.

Reported by: luporl via jhibbits
Reviewed by: luporl
X-MFC-With: r342771
Differential Revision: https://reviews.freebsd.org/D18777

Expose threads-per-core and physical core count information

With new sysctls (to the best of our ability do detect them). Restructured
smp.4 slightly for clarity (keep relevant stuff closer to the top) while
documenting.

Reviewed by: markj, jhibbits (ppc parts)
MFC after: 3 days
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D18322

Move the powerpc64 direct map base address from zero to high memory. This
accomplishes a few things:
- Makes NULL an invalid address in the kernel, which is useful for catching
bugs.
- Lays groundwork for radix-tree translation on POWER9, which requires the
direct map be at high memory.
- Similarly lays groundwork for a direct map on 64-bit Book-E.

The new base address is chosen as the base of the fourth radix quadrant
(the minimum kernel address in this translation mode) and because all
supported CPUs ignore at least the first two bits of addresses in real
mode, allowing direct-map addresses to be used in real-mode handlers.
This is required by Linux and is part of the architecture standard
starting in POWER ISA 3, so can be relied upon.

Reviewed by: jhibbits, Breno Leitao
Differential Revision: D14499

Honor physical memory regions marked unavailable in the FDT, when present.
The most notable of these is the FDT itself, which it is a bad idea to
overwrite.

Document places we assume that physical memory is direct-mapped at zero by
using a new macro PHYS_TO_DMAP, which deliberately has the same name as the
equivalent macro on amd64. This also sets the stage for moving the direct
map to another base address.

Change the way SMP startup works to match the new multi-AP features in
locore64.S introduced in r327358.

MFC after: 3 weeks

sys/powerpc: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

As <machine/pmap.h> is included from <vm/pmap.h>, there is no need to
include it explicitly when <vm/pmap.h> is already included.

Reviewed by: alc, kib
Differential Revision: https://reviews.freebsd.org/D5373

Use FDT properties to identify a PS3 if present.

Fix allocation of 128MB extended memory region, broken since some careless
modifications in December.

MFC after: 3 days

Rearchitect platform memory map parsing to make it less
Open Firmware-centric:
- Keep the static list of regions in platform.c instead of ofw_machdep.c
- Move various merging and sorting operations to platform.c as well
- Move apple_hacks code out of ofw_machdep.c and into platform_powermac.c,
where it belongs
- Move CHRP-specific dynamic-reconfiguration memory parsing into
platform_chrp.c instead of pretending it is shared code

MFcalloutng:
When CPU becomes idle, cpu_idleclock() calculates time to the next timer
event in order to reprogram hw timer. Return that time in sbintime_t to
the caller and pass it to acpi_cpu_idle(), where it can be used as one
more factor (quite precise) to extimate furter sleep time and choose
optimal sleep state. This is a preparatory change for further callout
improvements will be committed in the next days.

The commmit is not targeted for MFC.

Introduce PLATFORMMETHOD_END and use it.

Now that we can tolerate LPAR context switches on the PS3 hypervisor, going
to hypervisor-idle on both threads will not hang the kernel.

Import support for the Sony Playstation 3 using the OtherOS feature
available on firmwares 3.15 and earlier.

Caveats: Support for the internal SATA controller is currently missing,
as is support for framebuffer resolutions other than 720x480. These
deficiencies will be remedied soon.

Special thanks to Peter Grehan for providing the hardware that made this
port possible, and thanks to Geoff Levand of Sony Computer Entertainment
for advice on the LV1 hypervisor.