CVE-2025-39740

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

drm/xe/migrate: prevent potential UAF

If we hit the error path, the previous fence (if there is one) has
already been put() prior to this, so doing a fence_wait could lead to
UAF. Tweak the flow to do to the put() until after we do the wait.

(cherry picked from commit 9b7ca35ed28fe5fad86e9d9c24ebd1271e4c9c3e)