DVMDFSI compatibility with DIU3000

[jsb5151]

This issue is to track the enhancements required to make DVMDFSI work with the DIU3000.

[jsb5151]

Notes from troubleshooting: I set up 2 DIUs programmed identically, each one with their DVM-V24 board. First DIU had the old C#/dotnet version, and the 2nd one was running the new version. Here are my observations so far, based on traces on both sides.

- C# code sets a source flag on both VHDR1 & VHDR2 whereas C++ does it only on VHDR2

- LDU1 Voice 2 ($63) and LDU2 Voice frame 11 ($6C) have different sizes: (C++ has 13 bytes, C# has 14)
- P25Link code (thanks Wodie!) defines 0x63 and 0x6C frames as 14 bytes

- LDU 1 RS values are different ($67, $68, $69) but that's expected due to the different data

[jsb5151]

I guess we can close this since standalone DVMDFSI is deprecated.