hwc2 : Fix fence management issue during power state change

- Power state transitions (on and doze) are concurrently issued with a
  commit. The new commit gets a new release fence for the same pipes
  which were staged in previous cycle. The previous releases fence gets
  signaled at this point causing resource manager pipe fences in dangling
  state.

CRs-Fixed: 2265827
Change-Id: I5dfe9b004e6fc2a4e14e6b4085a032287066b5ce
4 files changed