Add proper support for AnyTone AT-D868UV

[hmatuschek]

trafficstars

As the AT-D868UVE is supported, it should be easy to implement the differences only. Also already got a wireshark capture of the read/write operation. Hence emulation for codeplug verification is possible. Note that currently, this device is handled as a D868UVE.

• [ ] Verify memory regions
• [ ] Verify channel encoding
• [ ] Verify zone encoding
• [ ] Verify contact encoding
• [ ] Verify analog contact encoding
• [ ] Verify scan list encoding
• [ ] Verify radio DMR ID encoding
• [ ] Verify DMR APRS encoding
• [ ] Verify general settings encoding
• [ ] Verify boot settings encoding
• [ ] Verify preset messages encoding
• [ ] Verify hot key settings encoding
• [ ] Verify FM broadcast channel encoding
• [ ] Verfy analog signalling (DTMF, 5-tone etc) encoding
• [ ] Verify DMR encryption encoding
• [ ] Verify call-sign DB encoding.