C2VdaBqBlockPool: change Fence::waitForever() to Fence::wait()

When running MediaSyncTest, Fence::waitForever() is stuck for few
seconds, and it blocks other methods due to the mutex. This CL changes
waitForever() method to wait() with timeout. Also we enlarge the
timeout to 32 ms.

Bug: 177484971
Test: android.media.cts.AdaptivePlaybackTest
Test: android.media.cts.MediaSyncTest#testPlayVideo

Change-Id: I6d8d2c3befed35e17e16f322edfaa4245797254c