clocksource/drivers/bcm2835_timer: Fix memory leak of timer

[ Upstream commit 2052d032c06761330bca4944bb7858b00960e868 ]

Currently when setup_irq fails the error exit path will leak the
recently allocated timer structure.  Originally the code would
throw a panic but a later commit changed the behaviour to return
via the err_iounmap path and hence we now have a memory leak. Fix
this by adding a err_timer_free error path that kfree's timer.

Addresses-Coverity: ("Resource Leak")
Fixes: 524a7f08 ("clocksource/drivers/bcm2835_timer: Convert init function to return error")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDaniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20191219213246.34437-1-colin.king@canonical.comSigned-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/clocksource/bcm2835_timer.c

@@ -134,7 +134,7 @@ static int __init bcm2835_timer_init(struct device_node *node)
 	ret = setup_irq(irq, &timer->act);
 	if (ret) {
 		pr_err("Can't set up timer IRQ\n");
-		goto err_iounmap;
+		goto err_timer_free;
 	}
 
 	clockevents_config_and_register(&timer->evt, freq, 0xf, 0xffffffff);
@@ -143,6 +143,9 @@ static int __init bcm2835_timer_init(struct device_node *node)
 
 	return 0;
 
+err_timer_free:
+	kfree(timer);
+
 err_iounmap:
 	iounmap(base);
 	return ret;