x86: use proper 'clac' and 'stac' opcode names

x86: use proper 'clac' and 'stac' opcode names

Back when we added SMAP support, all versions of binutils didn't
necessarily understand the 'clac' and 'stac' instructions.  So we
implemented those instructions manually as ".byte" sequences.

But we've since upgraded the minimum version of binutils to version
2.25, and that included proper support for the SMAP instructions, and
there's no reason for us to use some line noise to express them any
more.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>