Merge changes I660901a4,I73ef9a97,Iccfb31fe,If8adec40,Ie379258b, ...

* changes:
  Remove functions orphaned by the removal of BTM_VendorCleanup
  Remove unreachable BT(A|M)_VendorCleanup functions
  This call will never be successful
  Flatten bte_main_cleanup
  Move bte_main_cleanup call to stack_manager
  Rename bte_main_boot_entry, and pull out irrelevant module inits