drm/vc4: Call drm_dev_register() after all setup is done

drm_dev_register() initializes internal clients like bootsplash as the
last thing it does, so all setup needs to be done at this point.

Fix by calling vc4_kms_load() before registering.
Also check the error code returned from that function.

Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326175546.18126-17-noralf@tronnes.org

drivers/gpu/drm/vc4/vc4_drv.c

@@ -277,11 +277,13 @@ static int vc4_drm_bind(struct device *dev)
 
 	drm_fb_helper_remove_conflicting_framebuffers(NULL, "vc4drmfb", false);
 
-	ret = drm_dev_register(drm, 0);
+	ret = vc4_kms_load(drm);
 	if (ret < 0)
 		goto unbind_all;
 
-	vc4_kms_load(drm);
+	ret = drm_dev_register(drm, 0);
+	if (ret < 0)
+		goto unbind_all;
 
 	drm_fbdev_generic_setup(drm, 16);