clover: Local memory needs to be aligned.

clover: Local memory needs to be aligned.

Fixes a couple of OpenCL CTS tests.

v3:
* Add a comment in module.hpp explaining that target_align means
  something different for arguments of type local (Francisco Jerez)
* Squash in the fix for the LLVM backend.

Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Pierre Moreau <dev@pmoreau.org>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10256>