drm/xe: Refactor max_remote_tiles

max_remote_tiles is more related to the platform than the GT IP. Thus
move it to platform descriptor from graphics descriptor. Note that the
FIXME is no more required, thus it can be dropped.

v2: Rebase
v3: Change the position of comment (MattR)

Signed-off-by: Sai Teja Pottumuttu <sai.teja.pottumuttu@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250130085804.4136497-3-sai.teja.pottumuttu@intel.com


Signed-off-by: Matt Roper <matthew.d.roper@intel.com>