drm/xe/hw_engine: Fix double-free of managed BO in error path

In the Linux kernel, the following vulnerability has been resolved: drm/xe/hw_engine: Fix double-free of managed BO in error path The error path in hw_engine_init() explicitly frees a BO allocated with xe_managed_bo_create_pin_map() via xe_bo_unpin_map_no_vm(). Since the managed BO already has a devm cleanup action registered, this causes a double-free when devm unwinds during probe failure. Remove the explicit free and let devm handle it, consistent with all other xe_managed_bo_create_pin_map() callers. (cherry picked from commit e459a3bdeb117be496d7f229e2ea1f6c9fe4080b)