Since commit ba420afab565 ("drm/vkms: Bugfix racing hrtimer vblank
handle") the work is scheduled at vkms_vblank_simulate() and since
commit 5ef8100a3919 ("drm/vkms: flush crc workers earlier in commit
flow") the work is flushed at vkms_atomic_commit_tail(). Update function
commment to reflect that.