timekeeping: Fix ktime_add overflow in tk_set_wall_to_mono

euler inclusion
category: bugfix
Bugzilla: 5380
CVE: N/A
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Syzkaller report UBSAN bug:
UBSAN: Undefined behaviour in kernel/time/timekeeping.c:98:17
signed integer overflow:
8589935550743139462 + 2147483647000000000 cannot be represented
in type 'long long int'

Use add_time_safe instead add_time in tk_set_wall_to_mono.

Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Reviewed-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>