drm: bochs: drop unused struct fields

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/bochs/bochs_fbdev.c

@@ -190,7 +190,6 @@ int bochs_fbdev_init(struct bochs_device *bochs)
 	int ret;
 
 	bochs->fb.helper.funcs = &bochs_fb_helper_funcs;
-	spin_lock_init(&bochs->fb.dirty_lock);
 
 	ret = drm_fb_helper_init(bochs->dev, &bochs->fb.helper,
 				 1, 1);