- In the current situation the padding that is added is dangerous to write
  to, userspace could potentially overwrite parts of another bo.
- Depth and stencil buffers are supposed to be large enough in general so
  the waste of memory should be acceptable.
- Alternatives are hiding the padding from users or splitting vram into 2
  zones.
Signed-off-by: NMaarten Maathuis <madman2003@gmail.com>
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>