gpio: mb86s7x: Handle return value of clk_prepare_enable.

clk_prepare_enable() can fail here and we must check its return value.

Signed-off-by: Arvind Yadav <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/gpio/gpio-mb86s7x.c

···
 	if (IS_ERR(gchip->clk))
 		return PTR_ERR(gchip->clk);
 
-	clk_prepare_enable(gchip->clk);
+	ret = clk_prepare_enable(gchip->clk);
+	if (ret)
+		return ret;
 
 	spin_lock_init(&gchip->lock);