Merge changes Ia3a8c7e1,I65bac30e,Ide1a5faa,I64f5be7d,Id19aa6c9, ...

* changes:
  enum-ify bta/include/bta_api::BTA_DM_PM_
  Remove #def and use IsEprAvailable
  Use proper tHCI_STATUS types
  Inclusive language BTM_DEV_BLACKLISTED => BTM_DEV_RESTRICT_LISTED
  Properly retrieve acl_conn stack/acl/btm_acl::btm_read_remote_features_complete
  Properly retrieve acl_conn stack/acl/btm_acl::btm_read_remote_ext_features_complete
  Properly retrieve acl_conn stack/acl/btm_acl::btm_read_tx_power_complete
  Properly retrieve acl_conn stack/acl/btm_acl::btm_read_automatic_flush_timeout_complete
  Properly retrieve acl_conn stack/acl/btm_acl::btm_read_rssi_complete
  Re-log and properly type bta/dm/bta_dm_pm::bta_dm_pm_sniff
  Properly type bta/.../::BTA_SYS_CONN_OPEN
  Properly type args stack/acl/btm_pm::BTM_ReadPowerMode
  Add bta/sys/bta_sys::bta_sys_conn_status_text
  enum-ify bta/sys/bta_sys::tBTA_SYS_CONN_STATUS
  Add stack/include/btm_status::btm_status_text
  gd_acl: Remove redundant call stack/l2cap/l2c_link