drm/mgag200: check alloc_apertures() success in mga_vram_init()

Check for alloc_apertures() memory allocation failure, and propagate an
error code in case the allocation failed.

Signed-off-by: Tommi Rantala <tt.rantala@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
1 file changed