restore powerpc-darwin Ada bootstrap.

restore powerpc-darwin Ada bootstrap.

gcc:

	Backport from mainline (restore powerpc-darwin Ada bootstrap).
	* config/rs6000/rs6000.c (compute_save_world_info): Test
	cfun->has_nonlocal_label to determine if the out-of-line save
	world call may be used.

ada:

	Backport from mainline (restore powerpc-darwin Ada bootstrap).
	* gcc-interface/Makefile.in (darwin): Provide powerpc64 system
	implementation.
	* system-darwin-ppc64.ads: New file.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-4_6-branch@178680 138bc75d-0d04-0410-961f-82ee72b054a4