Merge changes I241a2915,I4281a4f0,Id0847f16,I459e99c4,Ia8aec848, ...

* changes:
  Fix proper headers to stack/acl/btm_acl::btm_cont_rswitch
  Move btm_pm_find_acl_ind() into stack/btm/btm_acl
  Add stack/acl/btm_acl APIs
  Declare and define tACL_CONN variables together
  Internally link stack/acl/btm_acl btm_establish_continue
  Shift stack/l2cap/l2c_ble.cc to use new API
  Move BTM_ReadConnectionAddr from btm to acl