Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Provide support in loader for booting 64-bit PowerPC kernels. Like amd64,
64-bit PowerPC kernels are loaded by a 32-bit loader, since nearly all
powerpc64 firmwares execute in 32-bit mode.

Clean up PowerPC loader(8) build config.

Turn off TFTP support by default: when both TFTP and NFS are enabled in the
loader, strange interactions occur in the pure netbooting scenario (i.e.
loader is TFTP-ed, kernel+world mounted over NFS), leading to very slow access
to the NFS-exported files.

Reviewed by: grehan
Approved by: cognet (mentor)

Forced commit to record that this file was repocopied from
src/sys/boot/powerpc/loader.

Repocopy by: simon@

Remove more Alpha bits from the boot code including fixing several
stale comments.

Convert to __FBSDID.

Update libstand filesystems to be in-line with tier-1 platforms.

Renamed the loader's zipfs to gzipfs. zipfs.c was repo-copied to gzipfs.c.

Mega-patch for OpenFirmware loader support.

- Flesh out ofw_readin routine.
- Add OpenFirmware load and exec routines.
- Make sure memory allocation for the kernel is done correctly.
- Change the way the heap is allocated so as to make it easier to deallocate
when we hand over.
- Add a command to print memory maps similar to the one for ia64.

With this patch, I can now load and hand over to a kernel on my iMac. There
are some problems with OpenFirmware routines failing after the hand over that
still need to be addressed.

OpenFirmware/PowerPC loader, part 2.

As of this patchset, the loader builds (under NetBSD/macppc), boots, interacts
and talks to BOOTP/NFS servers.

(main.c was moved from boot/ofw/libofw to boot/ofw/common but has no revision
history)

Reviewed by: obrien

The PowerPC conversion was

Submitted by: Benno Rice <benno@jeamland.net>

Convert from the Alpha compontents to PowerPC ones.

Update loader logic to distinguish modules vs. files.
Add support for module metadata. The old way of dependancy
handling will be supported for a while.

Reviewed by: peter

Teach the loader about the ext2fs filesystem, extended partitions, and
the new readdir function.

Add more missing files from the reorganisation.

Submitted by: dfr