* configure.tgt: Support powerpc-linux and powerpc-darwin.
	* config/linux/powerpc/futex_bits.h: New file.
	* config/powerpc/cacheline.h: New file.
	* config/powerpc/sjlj.S: New file.
	* config/powerpc/target.h: New file.
	* config/generic/asmcfi.h (cfi_offset): New.
	(cfi_restore, cfi_undefined): New.

From-SVN: r182930