Merge changes I4b15d054,Id53d86f3,Icc604d09,Ib19ee20d,I550d96d1, ...

* changes:
  Unify def tBTM_SEC_CBACK=>tBTM_SEC_CALLBACK
  Simplify stack/acl/btm_acl::btm_acl_created()
  Removed unused tACL_CONN fields
  Use API stack/acl/btm_acl
  Add APIs to stack/acl/btm_acl
  Use API stack/acl/btm_acl::btm_acl_connection_request
  Add API stack/acl/btm_acl::btm_acl_connection_request
  Wrap tL2C_LCB::link_role in API
  Rename btm_dev_support_switch
  Streamline stack/btm/btm_dev::btm_dev_support_switch
  Replace BTM_ACL_PKT_TYPES_MASK_