drm/fb-helper: Only consider active CRTCs for vblank sync
In the Linux kernel, the following vulnerability has been resolved: drm/fb-helper: Only consider active CRTCs for vblank sync Only synchronize fbdev output to the vblank of an active CRTC. Go over the list of CRTCs and pick the first that matches. Fixes warnings as the one shown below [ 77.201354] WARNING: drivers/gpu/drm/drm_vblank.c:1320 at drm_crtc_wait_one_vblank+0x194/0x1cc [drm], CPU#1: kworker/1:7/1867 [ 77.201354] omapdrm omapdrm.0: [drm] vblank wait timed out on crtc 0 This currently happens if the fbdev output is not on CRTC 0. Atomic and non-atomic drivers require distinct code paths. As for other fbdev operations, impleme