powerpc/lib/Makefile: Don't pull in quad.o for 32-bit kernels

powerpc/lib/Makefile: Don't pull in quad.o for 32-bit kernels

The functions exported by quad.o are only used when guarded by
__powerpc64__ and so are unused on 32-bit kernels. Moreover, their
implementations make use of instructions which will cause an illegal
instruction error on 32-bit processors, and are not accepted by the
assembler for SPE processors.

Fixes: 31bfdb036f12 ("powerpc: Use instruction emulation infrastructure to handle alignment faults")
Signed-off-by: James Clarke <jrtc27@jrtc27.com>
Gbp-Pq: Topic bugfix/powerpc
Gbp-Pq: Name powerpc-lib-makefile-don-t-pull-in-quad.o-for-32-bit.patch