drm/stm: Don't set allow_fb_modifiers explicitly

Since

commit 890880dd
Author: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Date:   Fri Jan 4 09:56:10 2019 +0100

    drm: Auto-set allow_fb_modifiers when given modifiers at plane init

this is done automatically as part of plane init, if drivers set the
modifier list correctly. Which is the case here.
Acked-by: Philippe Cornu <philippe.cornu@st.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Yannick Fertre <yannick.fertre@foss.st.com>
Cc: Philippe Cornu <philippe.cornu@foss.st.com>
Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-arm-kernel@lists.infradead.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210427092018.832258-7-daniel.vetter@ffwll.ch

drivers/gpu/drm/stm/ltdc.c

@@ -1326,8 +1326,6 @@ int ltdc_load(struct drm_device *ddev)
 		goto err;
 	}
 
-	ddev->mode_config.allow_fb_modifiers = true;
-
 	ret = ltdc_crtc_init(ddev, crtc);
 	if (ret) {
 		DRM_ERROR("Failed to init crtc\n");