Bluetooth: Call pre init API unconditionally

- Call pre init API un conditionally from Audio
  primary HAL as all valid checks have been
  already incorporated in the same API.

- Without this, VTS issues are seen as HIDL 2.0
  is not registered from pre init API which is
  not being called from Audio HAL due to older
  vendor frameworks API usage.

CRs-Fixed: 2493380
Change-Id: I12102426c6f280be2f2533ea7530a27f804e95b5