configs: Add aptxtws to supported offload for split A2DP

- BT host considers aptxtws (dual mono) as separate codec
  and end point.
- Offload cap property set in HAL is being used to enable
  or disable codecs in BT stack
- Add aptxtws as supported offload codec for split A2DP

Change-Id: I6ce18e87e2b1aa413a827b785c2f34b7e3943f4d