Fix effect volume cache issue.

1. Cache the requested volume instead of the returned volume from
   set volume command. The returned value is the one used to indicate
   the volume to all other effects in chain.
2. Cache the volume control effect so that there is not need to set the
   volume if the volume control effect is not changed.

Bug: 333015116
Test: atest VisualizerTest LoudnessEnhancerTest
Change-Id: Ifda65e6dd7094ba94a1220c66c3a553bb3c067bd