CVE-2022-50173 drm/msm/mdp5: Fix global state lock backoff

In the Linux kernel, the following vulnerability has been resolved: drm/msm/mdp5: Fix global state lock backoff We need to grab the lock after the early return for !hwpipe case. Otherwise, we could have hit contention yet still returned 0. Fixes an issue that the new CONFIGDRMDEBUGMODESETLOCK stu...