fix(el3-spmc): validate shmem descriptor alignment

If the size of a shmem descriptor is not a multiple of 16, the
descriptor would be unusable, but the problem would be caught much
later.

Change-Id: I907f3862b55c6341e39a6b8b2e24784127230478
Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
1 file changed