hal: Reset A2DP backend before SCO is started

- SCO and A2DP share the same Slimbus backend.
  During A2DP to SCO transition, A2DP sound device in
  audio HAL if disabled after SCO audio route is enabled
  overwrites SCO backend config with A2DP reset config.
- Reset A2DP config with A2DP suspension rather than
  wait for it to be handled from stop playback.
  Don't reset backend if stop playback is called
  while A2DP is suspended.
- Also, set/reset slimbus TX config only when usecase is
  LDAC ABR.

CRs-Fixed: 2325382
Change-Id: Ibde776364005a516ad0465b490b3ddc8a4d26c5e