Revert "posix-cpu-timers: Avoid undefined behaviour in timespec64_to_ns()"

hulk inclusion
category: bugfix
bugzilla: 185900, https://gitee.com/openeuler/kernel/issues/I4MOGB
CVE: NA

-----------------------------------------------

This reverts commit 2a3c5819.
Commit c0b52741 fixes undefined behaviour in timespec64_to_ns(),
so just revert it.
Signed-off-by: NYu Liao <liaoyu15@huawei.com>
Reviewed-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

kernel/time/posix-timers.c

@@ -877,14 +877,6 @@ static int do_timer_settime(timer_t timer_id, int flags,
 	if (!timespec64_valid(&new_spec64->it_interval) ||
 	    !timespec64_valid(&new_spec64->it_value))
 		return -EINVAL;
-	if (new_spec64->it_interval.tv_sec >= KTIME_SEC_MAX) {
-		new_spec64->it_interval.tv_sec = KTIME_SEC_MAX;
-		new_spec64->it_interval.tv_nsec = 0;
-	}
-	if (new_spec64->it_value.tv_sec >= KTIME_SEC_MAX) {
-		new_spec64->it_value.tv_sec = KTIME_SEC_MAX;
-		new_spec64->it_value.tv_nsec = 0;
-	}
 
 	if (old_spec64)
 		memset(old_spec64, 0, sizeof(*old_spec64));