drm/xe/sync: Cleanup partially initialized sync on parse failure

In the Linux kernel, the following vulnerability has been resolved:

drm/xe/sync: Cleanup partially initialized sync on parse failure

xe_sync_entry_parse() can allocate references (syncobj, fence, chain fence,

or user fence) before hitting a later failure path. Several of those paths

returned directly, leaving partially initialized state and leaking refs.

Route these error paths through a common free_sync label and call

xe_sync_entry_cleanup(sync) before returning the error.

(cherry picked from commit f939bdd9207a5d1fc55cced5459858480686ce22)