Bluetooth: Optimize the L2cap FCR tx timer

- Optimize the L2cap Flow control tx timer
  to avoid frequent start and stop of same
  timer.

- it will restart the timer instead of stop
  and start.

- Changes made in btm timer functions also
  to avoid scheduling of next timer in queue
  though is not required as the same timer
  is supposed to start.

CRs-Fixed: 934414
Change-Id: Idd43a71617a27c6d70fafa4e31c16f735a1a9425
2 files changed