clocksource/drivers/mtk_timer: Fix memleak in mtk_timer_init()

Add error path to clear evt struct allocated by kzalloc() in the beginning of
function mtk_timer_init().

Acked-by: Matthias Brugger <[e-mail]>
Signed-off-by: Alexey Klimov <[e-mail]>
Signed-off-by: Daniel Lezcano <[e-mail]>

drivers/clocksource/mtk_timer.c

···
 	evt->gpt_base = of_io_request_and_map(node, 0, "mtk-timer");
 	if (IS_ERR(evt->gpt_base)) {
 		pr_err("Can't get resource\n");
-		return;
+		goto err_kzalloc;
 	}
 
 	evt->dev.irq = irq_of_parse_and_map(node, 0);
···
 	iounmap(evt->gpt_base);
 	of_address_to_resource(node, 0, &res);
 	release_mem_region(res.start, resource_size(&res));
+err_kzalloc:
+	kfree(evt);
 }
 CLOCKSOURCE_OF_DECLARE(mtk_mt6577, "mediatek,mt6577-timer", mtk_timer_init);