drm/xe: Prevent VFs from exposing the CCS mode sysfs file

drm/xe: Prevent VFs from exposing the CCS mode sysfs file

Skip creating CCS sysfs files in VF mode to ensure VFs do not
try to change CCS mode, as it is predefined and immutable in
the SR-IOV mode.

Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Nareshkumar Gollakoti <naresh.kumar.g@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20260202170810.1393147-5-naresh.kumar.g@intel.com
(cherry picked from commit 4e8f602ac3574cf1ebc7acfb6624d06e04b30c91)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>