drm/xe/pf: Disable PF restart worker on device removal

drm/xe/pf: Disable PF restart worker on device removal

We can't let restart worker run once device is removed, since other
data that it might want to access could be already released.
Explicitly disable worker as part of device cleanup action.

Fixes: a4d1c5d0b99b ("drm/xe/pf: Move VFs reprovisioning to worker")
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Cc: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://lore.kernel.org/r/20250801142822.180530-2-michal.wajdeczko@intel.com
(cherry picked from commit a424353937c24554bb242a6582ed8f018b4a411c)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>