drm/xe/uapi: Remove GT_TYPE_REMOTE

drm/xe/uapi: Remove GT_TYPE_REMOTE

With the split between tile and gt, this is currently unused.
Also it is bringing confusion because main vs remote would be
more a concept of the tile itself and not about GT.

So, the MAIN one is the traditional GT used for every operation
in older platforms, and for render/graphics and compute on platforms
that contains the stand-alone Media GT.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Francois Dugast <francois.dugast@intel.com>
Cc: Carl Zhang <carl.zhang@intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>