drm/pl111: Make sure of_device_id tables are NULL terminated

We prefer to of_device_id tables are NULL terminated. So make
vexpress_muxfpga_match is NULL terminated.
Signed-off-by: Nzhong jiang <zhongjiang@huawei.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1533379767-15629-1-git-send-email-zhongjiang@huawei.comSigned-off-by: NSean Paul <seanpaul@chromium.org>

drivers/gpu/drm/pl111/pl111_vexpress.c

@@ -111,7 +111,8 @@ static int vexpress_muxfpga_probe(struct platform_device *pdev)
 }
 
 static const struct of_device_id vexpress_muxfpga_match[] = {
-	{ .compatible = "arm,vexpress-muxfpga", }
+	{ .compatible = "arm,vexpress-muxfpga", },
+	{}
 };
 
 static struct platform_driver vexpress_muxfpga_driver = {