moxa view: show more IOCs using port

It would be nice if the moxa view could show the IOC using the port in all cases, currently it looks for a macro in the config but the same macro name may not always be used. I wonder if we could hook directly into `drvAsynSerialPortConfigure` i.e. when an IOC calls this it will log the COM port and IOC/process name centrally which can then be picked up. This is a bit like how we currently get an IOC to log their PVs into mysql.