- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

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

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

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

Revert r253748,253749

This WIP should not have been committed yet.

Pointyhat to: avg

remove needless inclusion of machine/cpu.h in userland

MFC after: 21 days

Fix some ifdef logic in the libc syncicache() bit that I somehow missed in the
last commit. Now it really can use a runtime-set cacheline size.

Allow the cacheline size on PowerPC to be set at runtime. This is essential for
supporting 64-bit CPUs, which often have 128-byte cache lines instead of the
standard 32.

Fix bogon in previous commit: <machine/cpu.h> is still needed.

The definition of CACHELINESIZE moved from <machine/cpu.h> to
<machine/md_var.h>.

Include <stdlib.h> to get abort() prototype.

Minimal libc for PowerPC.

Reviewed by: benno

Approved by: re (blanket)