CVE-2024-56552 drm/xe/guc_submit: fix race around suspend_pending

In the Linux kernel, the following vulnerability has been resolved: drm/xe/gucsubmit: fix race around suspendpending Currently in some testcases we can trigger: xe 0000:03:00.0: drm Assertion execqueuedestroyedq failed! .... WARNING: CPU: 18 PID: 2640 at drivers/gpu/drm/xe/xegucsubmit.c:1826...