lantiq: use devm for mutex_init

It's common to avoid calling mutex_destroy when done. It's not correct strictly speaking.

Signed-off-by: Rosen Penev <[email protected]>
Link: https://github.com/openwrt/openwrt/pull/16832
Signed-off-by: Hauke Mehrtens <[email protected]>
(cherry picked from commit fccff963c0a6ba035455daea61566f4d121643e3)
Link: https://github.com/openwrt/openwrt/pull/17097
Signed-off-by: Petr Štetiar <[email protected]>

target/linux/lantiq/patches-6.6/0008-MIPS-lantiq-backport-old-timer-code.patch

@@ -186,7 +186,7 @@ Signed-off-by: John Crispin <[email protected]>
  obj-y += vmmc.o
 --- /dev/null
 +++ b/arch/mips/lantiq/xway/timer.c
-@@ -0,0 +1,886 @@
+@@ -0,0 +1,888 @@
 +#ifndef CONFIG_SOC_AMAZON_SE
 +
 +#include <linux/kernel.h>
@@ -989,7 +989,9 @@ Signed-off-by: John Crispin <[email protected]>
 +	ltq_w32(0xfff, LQ_GPTU_IRNCR);
 +
 +	memset(&timer_dev, 0, sizeof(timer_dev));
-+	mutex_init(&timer_dev.gptu_mutex);
++	ret = devm_mutex_init(&pdev->dev, &timer_dev.gptu_mutex);
++	if (ret)
++		return ret;
 +
 +	lq_enable_gptu();
 +	timer_dev.number_of_timers = GPTU_ID_CFG * 2;