pinctrl: sh-pfc: Unlock on error in sh_pfc_func_set_mux()

We need to unlock and enable IRQs before we return on this error path.

Fixes: 8a0cc47ccc ("pinctrl: sh-pfc: Rollback to mux if required when the gpio is freed")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20190827093927.GB8443@mwanda
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/sh-pfc/pinctrl.c

@@ -361,8 +361,10 @@ static int sh_pfc_func_set_mux(struct pinctrl_dev *pctldev, unsigned selector,
 		 * This driver cannot manage both gpio and mux when the gpio
 		 * pin is already enabled. So, this function fails.
 		 */
-		if (cfg->gpio_enabled)
-			return -EBUSY;
+		if (cfg->gpio_enabled) {
+			ret = -EBUSY;
+			goto done;
+		}
 
 		ret = sh_pfc_config_mux(pfc, grp->mux[i], PINMUX_TYPE_FUNCTION);
 		if (ret < 0)