Clean A2DP dump output

Before:
  TxQueue:
    Counts (enqueue/dequeue/readbuf)                        : 0 / 0 / 0
    Last update time ago in ms (enqueue/dequeue/readbuf)    : 0 / 0 / 0
    Frames per packet (total/max/ave)                       : 0 / 0 / 0
    Counts (flushed/dropped/dropouts)                       : 0 / 0 / 0
    Last update time ago in ms (flushed/dropped)            : 0 / 0
    Counts (underflow/underrun)                             : 0 / 0
    Bytes (underflow/underrun)                              : 0 / 0
    Last update time ago in ms (underflow/underrun)         : 0 / 0
    Enqueue deviation counts (overdue/premature)            : 0 / 0
    Enqueue overdue scheduling time in ms (total/max/ave)   : 0 / 0 / 0
    Enqueue premature scheduling time in ms (total/max/ave) : 0 / 0 / 0
    Dequeue deviation counts (overdue/premature)            : 0 / 0
    Dequeue overdue scheduling time in ms (total/max/ave)   : 0 / 0 / 0
    Dequeue premature scheduling time in ms (total/max/ave) : 0 / 0 / 0

After:  
  TxQueue:
  Counts (enqueue/dequeue/readbuf)                        : 0 / 0 / 0
  Last update time ago in ms (enqueue/dequeue/readbuf)    : 0 / 0 / 0
  Frames per packet (total/max/ave)                       : 0 / 0 / 0
  Counts (flushed/dropped/dropouts)                       : 0 / 0 / 0
  Last update time ago in ms (flushed/dropped)            : 0 / 0
  Counts (underflow/underrun)                             : 0 / 0
  Bytes (underflow/underrun)                              : 0 / 0
  Last update time ago in ms (underflow/underrun)         : 0 / 0
  Enqueue deviation counts (overdue/premature)            : 0 / 0
  Enqueue overdue scheduling time in ms (total/max/ave)   : 0 / 0 / 0
  Enqueue premature scheduling time in ms (total/max/ave) : 0 / 0 / 0
  Dequeue deviation counts (overdue/premature)            : 0 / 0
  Dequeue overdue scheduling time in ms (total/max/ave)   : 0 / 0 / 0
  Dequeue premature scheduling time in ms (total/max/ave) : 0 / 0 / 0

Bug: 27294154
Change-Id: I2952ceed7b02db0d8497b67de0f57e4f9128e5bf