drm/xe: add MMIO extension support flags

Besides the regular MMIO space that exists by default, MMIO
extension support & MMIO extension tile size should both be
defined per device, and updated from the device's descriptor.

Signed-off-by: Koby Elbaz <kelbaz@habana.ai>
Reviewed-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Moti Haimovski <mhaimovski@habana.ai>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>