drm/virtio: Wake up all waiters when capset response comes in.

If multiple callers occur simultaneously, wake them all up.
Signed-off-by: NDavid Riley <davidriley@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20190605234423.11348-2-davidriley@chromium.orgSigned-off-by: NGerd Hoffmann <kraxel@redhat.com>

drivers/gpu/drm/virtio/virtgpu_vq.c

@@ -598,7 +598,7 @@ static void virtio_gpu_cmd_capset_cb(struct virtio_gpu_device *vgdev,
 		}
 	}
 	spin_unlock(&vgdev->display_info_lock);
-	wake_up(&vgdev->resp_wq);
+	wake_up_all(&vgdev->resp_wq);
 }
 
 static int virtio_get_edid_block(void *data, u8 *buf,