re PR libffi/41908 (closures fail for some structure arguments containing floats)

	PR libffi/41908
	* src/x86/ffi64.c (classify_argument): Update from
	gcc/config/i386/i386.c.
	(ffi_closure_unix64_inner): Do not use the address of two consecutive
	SSE registers directly.
	* testsuite/libffi.call/cls_dbls_struct.c (main): Remove xfail
	for x86_64 linux targets.

From-SVN: r154988