* src/powerpc/ffi.c (ffi_prep_args64): Modify for changed gcc
	structure passing.
	(ffi_closure_helper_LINUX64): Likewise.
	* src/powerpc/linux64.S: Remove code writing to parm save area.
	* src/powerpc/linux64_closure.S (ffi_closure_LINUX64): Use return
	address in lr from ffi_closure_helper_LINUX64 call to calculate
	table address.  Optimize function tail.

From-SVN: r70050