fbdev: omapfb: delete check_required_callbacks()

Commit 561eb9d09a93 ("fbdev: omap/lcd: Make callbacks optional") made
panel callbacks optional but forgot to update check_required_callbacks().
As a result many (all?) OMAP systems using omapfb will crash at boot.
Fix by deleting the whole function.

Fixes: 561eb9d09a93 ("fbdev: omap/lcd: Make callbacks optional")
Signed-off-by: Aaro Koskinen <[e-mail]>
Cc: Tomi Valkeinen <[e-mail]>
Cc: Lars-Peter Clausen <[e-mail]>
Signed-off-by: Bartlomiej Zolnierkiewicz <[e-mail]>

drivers/video/fbdev/omap/omapfb_main.c

···
 	return 0;
 }
 
-static void check_required_callbacks(struct omapfb_device *fbdev)
-{
-#define _C(x) (fbdev->ctrl->x != NULL)
-#define _P(x) (fbdev->panel->x != NULL)
-	BUG_ON(fbdev->ctrl == NULL || fbdev->panel == NULL);
-	BUG_ON(!(_C(init) && _C(cleanup) && _C(get_caps) &&
-		 _C(set_update_mode) && _C(setup_plane) && _C(enable_plane) &&
-		 _P(init) && _P(cleanup) && _P(enable) && _P(disable) &&
-		 _P(get_caps)));
-#undef _P
-#undef _C
-}
-
 /*
  * Called by LDM binding to probe and attach a new device.
  * Initialization sequence:
···
 	if (fbdev->ctrl->mmap != NULL)
 		omapfb_ops.fb_mmap = omapfb_mmap;
 	init_state++;
-
-	check_required_callbacks(fbdev);
 
 	r = planes_init(fbdev);
 	if (r)