Get Bluetooth Class of Device

Modifies the native Bluetooth stack to
 1) return default value from BTA_DM_COD configuration when not set, and
 2) return adapter COD value even before stack start for Java Android
 stack.

Bug: 36015415
Test: Verified fetching of COD both before and after modification of
CoD value and restart of machine.

Change-Id: Ibcf726dcd7bea5d7e27c7a775f8cf7ea3f9e4107