[turbofan] Add turbofan support for PPC.

Conflicts:

	src/compiler/compiler.gyp
	src/globals.h
	test/cctest/compiler/call-tester.h
PPC: turbofan changes [08b12bb..2f0cfa9]
PPC: turbofan fixes.
PPC: turbofan changes [379040e..32f3277]
AIX: Request that GCC use fp rounding instructions.

The AIX math library has some non-standard behavior for ceil, trunc
and round.  The instructions frip, friz and frin return the desired
results.
Teach TurboFan to call C functions with result_size > 1.

Happily, this fixes WIN64 failures too.

BUG=
R=titzer@chromium.org

Review URL: https://codereview.chromium.org/709033002

Cr-Commit-Position: refs/heads/master@{#25216}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25216 ce2b1a6d-e550-0410-aec6-3dcde31c8c00