drm/bridge: vga-dac: Fix edid memory leak

edid should be freed once it's finished being used.

Fixes: 56fe8b6f ("drm/bridge: Add RGB to VGA bridge support")
Cc: Rob Herring <robh@kernel.org>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: <stable@vger.kernel.org> # v4.9+
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180420190007.1572-1-seanpaul@chromium.org

drivers/gpu/drm/bridge/dumb-vga-dac.c

@@ -56,7 +56,9 @@ static int dumb_vga_get_modes(struct drm_connector *connector)
 	}
 
 	drm_mode_connector_update_edid_property(connector, edid);
-	return drm_add_edid_modes(connector, edid);
+	ret = drm_add_edid_modes(connector, edid);
+	kfree(edid);
+	return ret;
 
 fallback:
 	/*