drm/panel: simple: Fix innolux_g121i1_l01 bus_format

innolux_g121i1_l01 sets bpc to 6, so use the corresponding bus format:
MEDIA_BUS_FMT_RGB666_1X7X3_SPWG.

Fixes: 4ae13e4 ("drm/panel: simple: Add more properties to Innolux G121I1-L01")
Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220826165021.1592532-1-festevam@denx.de

Author: hsdenx

drivers/gpu/drm/panel/panel-simple.c

@@ -2257,7 +2257,7 @@ static const struct panel_desc innolux_g121i1_l01 = {
 		.enable = 200,
 		.disable = 20,
 	},
-	.bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
+	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };