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

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

Change index() and rindex() to a weak alias.

This allows people to still write statically linked applications that
call strchr() or strrchr() and have a local variable or function called
index.

Discussed with: bde@

Merge index() and strchr() together.

As I looked through the C library, I noticed the FreeBSD MIPS port has a
hand-written version of index(). This is nice, if it weren't for the
fact that most applications call strchr() instead.

Also, on the other architectures index() and strchr() are identical,
meaning we have two identical pieces of code in the C library and
statically linked applications.

Solve this by naming the actual file strchr.[cS] and let it use
__strong_reference()/STRONG_ALIAS() to provide the index() routine. Do
the same for rindex()/strrchr().

This seems to make the C libraries and static binaries slightly smaller,
but this reduction in size seems negligible.

Merge jmallett@'s n64 work into HEAD - changeset 1.

Update libc assembly code to use macros that work on both o32 and n64.
Merge string functions from NetBSD.

The changes are from http://svn.freebsd.org/base/user/jmallett/octeon

Approved by: rrs (mentor), jmallett

Add mips support libc from the mips2-jnpr branch of perforce.