vl/dri: add color depth to vl winsys

For VDPAU use later

Signed-off-by: Leo Liu <leo.liu@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>

src/gallium/auxiliary/vl/vl_winsys.h

@@ -70,6 +70,7 @@ struct vl_screen
    struct pipe_loader_device *dev;
 
    void *xcb_screen;
+   uint32_t color_depth;
 };
 
 #ifdef HAVE_X11_PLATFORM

src/gallium/auxiliary/vl/vl_winsys_dri3.c

@@ -835,6 +835,7 @@ vl_dri3_screen_create(Display *display, int screen)
       free(geom_reply);
       goto close_fd;
    }
+   scrn->base.color_depth = geom_reply->depth;
    free(geom_reply);
 
    if (pipe_loader_drm_probe_fd(&scrn->base.dev, fd))