iec_61883_iidc_format::to_string() does not encode UT bit #391
Description
IEEE1722 format names as generated by iec_61883_iidc_format::to_string() (and aaf_format::to_string()) are used extensively throughout the command line app.
Hovewer, the "upto" bit (UT bit), though existent in the class, is not encoded in the format name. So, when listing supported formats of an entity using the "view descriptor" command, it's not clear if formats with less channels than listed are supported by the entity.
If I understand the according passage in the standard correctly, an entity shall use the UT bit to signal that it supports less channels than encoded in the format. But in a SET_STREAM_FORMAT cmd issued by a controller, the UT bit must not be set, instead the actual numbers of channels is encoded in the format.
In order to detect if a specific channel count is supported, it would be quite helpful if the UT bit was encoded in the format name, e.g.: IEC61883-6_AM824_MBLA_44.1KHZ_UT_5CH
I'm happy to help with a pull request to get this into the library! Or is there a reason why it hasn't been done before?