alarmtimer: Remove unnecessary initialization of variable 'ret'

ret is assigned before checked, so it does not need to initialize the
variable
Signed-off-by: Li zeming <zeming@nfschina.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230609182856.4660-1-zeming@nfschina.com

kernel/time/alarmtimer.c

@@ -847,7 +847,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
 	struct restart_block *restart = &current->restart_block;
 	struct alarm alarm;
 	ktime_t exp;
-	int ret = 0;
+	int ret;
 
 	if (!alarmtimer_get_rtcdev())
 		return -EOPNOTSUPP;