Revert "timekeeping: Avoid undefined behaviour in 'ktime_get_with_offset()'"

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

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This reverts commit 85d6dbdf.
Commit 7a8e61f8 force upper bound for setting CLOCK_REALTIME.
The realtime is limited, 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/timekeeping.c

@@ -798,7 +798,7 @@ ktime_t ktime_get_with_offset(enum tk_offsets offs)
 
 	do {
 		seq = read_seqcount_begin(&tk_core.seq);
-		base = ktime_add_safe(tk->tkr_mono.base, *offset);
+		base = ktime_add(tk->tkr_mono.base, *offset);
 		nsecs = timekeeping_get_ns(&tk->tkr_mono);
 
 	} while (read_seqcount_retry(&tk_core.seq, seq));