Merge changes I8f61001c,I52dafb82,I79d5fec6,I344fe614,I8c96c500, ... into main

* changes:
  Remove unused function gatt_num_clcb_by_bd_addr
  Remove unused functions btsock_thread_post_cmd, btsock_thread_remove_fd_and_close
  Remove unused legacy HCI command serializers
  Remove unused function btm_read_link_quality_timeout
  Remove unused function btm_queue_start_sync_req
  Remove unused function BTM_IsAclConnectionUpFromHandle
  Remove unused function btm_is_sco_active
  Remove unused functions btm_inq_db_init, btm_inq_db_free
  Remove unused function btm_dev_support_role_switch
  Remove unused module BtifConfigCache
  Remove debug function btif_debug_config_dump