audioflinger: Add tracing of buffer frames to PatchTrack/Record

Seeing requested / obtained buffer frame counts in trace
helps to identify discontinuities in software patch pipeline.

There is no need to trace requested frame count for PatchRecord
as it always requests as much as possible ("-1" frameCount).

Bug: 117564323
Test: with software patch active,
      external/chromium-trace/systrace.py audio

Merged-In: I78400f6cc1d1940b3290fb23bb1aacfbffe042e5
Change-Id: I78400f6cc1d1940b3290fb23bb1aacfbffe042e5