Revert "drm/fbdev: Fallback to non tiled mode if all tiles not present"

[ Upstream commit f053c83a ]

This reverts commit f25c7a00

 ("drm/fbdev: Fallback to non tiled mode
if all tiles not present"). The commit causes flip done timeouts in CI.

Below are the sample errors thrown in logs:

[IGT] core_getversion: executing
[IGT] core_getversion: exiting, ret=0
Setting dangerous option reset - tainting kernel
drm:drm_atomic_helper_wait_for_dependencies] ERROR [CRTC:152:pipe B] flip_done timed out
drm:drm_atomic_helper_wait_for_dependencies] ERROR [CONNECTOR:299:DP-2] flip_done timed out
drm:drm_atomic_helper_wait_for_dependencies] ERROR [PLANE:92:plane 1B] flip_done timed out
[drm:drm_atomic_helper_wait_for_flip_done] ERROR [CRTC:152:pipe B] flip_done timed out
[drm:drm_atomic_helper_wait_for_dependencies] ERROR [CRTC:152:pipe B] flip_done timed out
[drm:drm_atomic_helper_wait_for_dependencies] ERROR [CONNECTOR:299:DP-2] flip_done timed out
[drm:drm_atomic_helper_wait_for_dependencies] ERROR [PLANE:92:plane 1B] flip_done timed out
[drm:drm_atomic_helper_wait_for_flip_done] ERROR [CRTC:152:pipe B] flip_done timed out
Console: switching to colour frame buffer device 480x135
[drm:drm_atomic_helper_wait_for_dependencies] ERROR [CRTC:152:pipe B] flip_done timed out
[drm:drm_atomic_helper_wait_for_dependencies] ERROR [CONNECTOR:299:DP-2] flip_done timed out

Reverting the change for now to unblock CI execution.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Fixes: f25c7a00

 ("drm/fbdev: Fallback to non tiled mode if all tiles not present")
Closes: https://gitlab.freedesktop.org/drm/intel/issues/6
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191123091840.32382-1-uma.shankar@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>