Release RefreshRateOveray's SurfaceControl on the main thread

SurfaceControl assumes that its destruction happens without
SurfaceFlinger::mStateLock held, otherwise it causes a deadlock.

Bug: 237485868
Test: Enable refresh rate overlay and change resolution
Change-Id: I152586aaaf414ed0b90a6e6a8d78e867146ab96c
Merged-In: I152586aaaf414ed0b90a6e6a8d78e867146ab96c