drm/xe: Allocate dedicated workqueue for SR-IOV workers

We plan to use several workers where we might be running long
operations. Allocate dedicated workqueue to avoid undesired
interaction with non-virtualized workers.

Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://lore.kernel.org/r/20240104222031.277-2-michal.wajdeczko@intel.com


Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>