drm/xe/guc: Ensure CT state transitions via STOP before DISABLED

drm/xe/guc: Ensure CT state transitions via STOP before DISABLED

The GuC CT state transition requires moving to the STOP state before
entering the DISABLED state. Update the driver teardown sequence to make
the proper state machine transitions.

Fixes: ee4b32220a6b ("drm/xe/guc: Add devm release action to safely tear down CT")
Cc: stable@vger.kernel.org
Signed-off-by: Zhanjun Dong <zhanjun.dong@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260310225039.1320161-6-zhanjun.dong@intel.com