drm/bridge: tc358768: select CONFIG_VIDEOMODE_HELPERS

A dependency on this feature was recently introduced:

x86_64-linux-ld: vmlinux.o: in function `tc358768_bridge_pre_enable':
tc358768.c:(.text+0xbe3dae): undefined reference to `drm_display_mode_to_videomode'

Make sure this is always enabled.

Fixes: e5fb216 ("drm/bridge: tc358768: Use struct videomode")
Signed-off-by: Arnd Bergmann <[email protected]>
Reviewed-by: Neil Armstrong <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Neil Armstrong <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

Author: arndb

drivers/gpu/drm/bridge/Kconfig

@@ -313,6 +313,7 @@ config DRM_TOSHIBA_TC358768
 	select REGMAP_I2C
 	select DRM_PANEL
 	select DRM_MIPI_DSI
+	select VIDEOMODE_HELPERS
 	help
 	  Toshiba TC358768AXBG/TC358778XBG DSI bridge chip driver.