CVE-2026-72360: drm/xe/pf: Don't attempt to process FAST_REQ or EVENT relays

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

drm/xe/pf: Don't attempt to process FASTREQ or EVENT relays

Currently defined VF/PF relay actions use regular REQUEST messages only and the PF shouldn't attempt to handle FASTREQUEST nor EVENT messages as this would result in breaking the VFPF ABI protocol and also might trigger an assert on the PF side.

(cherry picked from commit 1714d360fc5ae2e0886a69e979095d9c7ff3568a)