Previously we misaligned stack by 8 in startup.S and compensated
	for it in callwrap.S. According to ABI docs (EFI and sysv amd64)
	right behaviour is to align stack in startup.S and keep it aligned
	in callwrap.S. startup.S part was committed few commits before. This
	takes care of callwrap.S.
	Reported by: Gary Lin.