drm/vc4: hdmi: Set default state margin at reset

Now that the TV margins are properly parsed and filled into
drm_cmdline_mode, we just need to initialise the first state at reset to
get those values and start using them.
Acked-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/44e24172e300be6a41578517021ef6a6e90ed682.1560783090.git-series.maxime.ripard@bootlin.com

drivers/gpu/drm/vc4/vc4_hdmi.c

@@ -255,11 +255,17 @@ static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)
 	return ret;
 }
 
+static void vc4_hdmi_connector_reset(struct drm_connector *connector)
+{
+	drm_atomic_helper_connector_reset(connector);
+	drm_atomic_helper_connector_tv_reset(connector);
+}
+
 static const struct drm_connector_funcs vc4_hdmi_connector_funcs = {
 	.detect = vc4_hdmi_connector_detect,
 	.fill_modes = drm_helper_probe_single_connector_modes,
 	.destroy = vc4_hdmi_connector_destroy,
-	.reset = drm_atomic_helper_connector_reset,
+	.reset = vc4_hdmi_connector_reset,
 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 };