drm: panel: Fix bus format for OrtusTech COM43H4M85ULC panel

The OrtusTech COM43H4M85ULC panel is a 18-bit RGB panel, set the bus
format to MEDIA_BUS_FMT_RGB666_1X18.

Fixes: 725c9d40f3fe ("drm/panel: Add support for OrtusTech COM43H4M85ULC panel")
Signed-off-by: Laurent Pinchart <[e-mail]>
Signed-off-by: Sam Ravnborg <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

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

···
 		.width = 56,
 		.height = 93,
 	},
-	.bus_format = MEDIA_BUS_FMT_RGB888_1X24,
+	.bus_format = MEDIA_BUS_FMT_RGB666_1X18,
 	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
 	.connector_type = DRM_MODE_CONNECTOR_DPI,
 };