drm/xe: Update query uapi to support standalone media

drm/xe: Update query uapi to support standalone media

Now that a higher GT count can result from either multiple tiles (with
one GT each) or an extra media GT within the root tile, we need to
update the query code slightly to stop looking at tile_count.

FIXME: As noted previously, we need to decide on a formal direction for
exposing tiles and/or GTs to userspace.

v2:
 - Drop num_gt() function in favor of stored xe->info.gt_count.  (Brian)
v3:
 - Keep XE_QUERY_GT_TYPE_REMOTE around for now.  Userspace probably
   doesn't actually need this, and we may remove it in the future, but
   for now let's avoid changing uapi.  (Brian)

Cc: Brian Welty <brian.welty@intel.com>
Reviewed-by: Brian Welty <brian.welty@intel.com>
Link: https://lore.kernel.org/r/20230601215244.678611-30-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>