drm/omapdrm: don't call drm_helper_disable_unused_functions

It's a legacy helper function which won't do good with atomic helpers.

Cc: Tomi Valkeinen <[e-mail]>
Cc: Laurent Pinchart <[e-mail]>
Acked-by: Laurent Pinchart <[e-mail]>
Acked-by: Tomi Valkeinen <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>
Link: http://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/omapdrm/omap_fbdev.c

···
 	if (ret)
 		goto fini;
 
-	/* disable all the possible outputs/crtcs before entering KMS mode */
-	drm_helper_disable_unused_functions(dev);
-
 	ret = drm_fb_helper_initial_config(helper, 32);
 	if (ret)
 		goto fini;