pata_arasan_cf: add missing clk_disable_unprepare() on error path

Add the missing clk_disable_unprepare() before return from cf_init()
in the error handling case.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/ata/pata_arasan_cf.c

@@ -319,6 +319,7 @@ static int cf_init(struct arasan_cf_dev *acdev)
 	ret = clk_set_rate(acdev->clk, 166000000);
 	if (ret) {
 		dev_warn(acdev->host->dev, "clock set rate failed");
+		clk_disable_unprepare(acdev->clk);
 		return ret;
 	}