shrink the latch waiting list (#4844)
shrink the latch waiting list (#4844)

Signed-off-by: zhangjinpeng1987 <0be30061b56e3ccbb0c7506bec92d245aba78ed7@pingcap.com>
BusyJay/tikv,pingcap/tikv,c4pt0r/tikv,BusyJay/tikv,BusyJay/tikv,BusyJay/tikv,pingcap/tikv