clk: rockchip: release io resource when failing to init clk

We should call iounmap to relase reg_base since it's not going
to be used any more if failing to init clk.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

drivers/clk/rockchip/clk-rk3188.c

@@ -773,6 +773,7 @@ static struct rockchip_clk_provider *__init rk3188_common_clk_init(struct device
 	ctx = rockchip_clk_init(np, reg_base, CLK_NR_CLKS);
 	if (IS_ERR(ctx)) {
 		pr_err("%s: rockchip clk init failed\n", __func__);
+		iounmap(reg_base);
 		return ERR_PTR(-ENOMEM);
 	}