Feature - Added channel INTERLOCK functionality

[dvanderlocht]

Added feature to interlock channels with the same interlock number configured to share DCD and PTT signaling. Useful with several setup types where 2 or more channels shouldn't interfere with eachother without the need to use TXINH and (external) connections and/or circuitry to accomplish similar goals.

For example when radios and/or antennas are shared, or RX/TX more than 1 mode on a single soundcard and radio (with 'virtual Y-cable' setup) using multiple Direwolf channels.

Channels on the same INTERLOCK number configured are sharing DCD and PTT signaling internally.

[wb2osz]

This is an interesting idea. I need more time to think about it. Reopening.

[dranch]

While you're thinking about it, I have always wanted Direwolf to have the ability to QSY the radio to different frequencies. Hamlib support is already there so linking these features together for say a "scanner / responder" would be very interesting

[dvanderlocht]

Closed this due to a minor flaw in the code causing a 'stuck DCD' state. I (already) have updated code which seems to fix the spotted issue. Now testing for a couple of weeks on my setup before committing.