mips: only define SYSCALL_ALIGN_64BIT for O32 ABIs
mips: only define SYSCALL_ALIGN_64BIT for O32 ABIs

The 64bit register alignment issue only affects the O32 ABI, so wrap
the define accordingly.  We don't want this being used for N32 ABIs.

This doesn't directly affect the N64 ABI since these files wouldn't
even be compiled for those targets (no need for the 32bit/64bit shim).

Signed-off-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@gentoo.org>

joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc