Re-use reference timing for late hint in SF hint session timing

Late hint in SF hint sessions currently mis-times the HWC present call
waiting for the next valid vsync, since it ignores this time when
determining where HWC started waiting for the release fence, but this
time needs to be included for late hint since it estimates its own
reference frame where this delay occurs. This whole issue can be
circumvented by just re-using reference frame timing in late hint since
it should just be the same.

Bug: b/236741803
Bug: b/195990840
Test: manual testing
Change-Id: I464c29902756658344768602247f9f15ca26fb1a