[chirp_devel] IC2730 Issue #7031 patch

[Dan Smith]

> Patch for issue #7031 to fix corrupted bank index values after download from IC-2730A. Possible cause of the bad values is use of an audio extension cable with the standard USB cable.

If this is the case, then anything could be corrupted, so spot fixes like this are ill-fated. It looks to me like we're not actually checking the checksum on received data frames on the icom base driver. We should do that and abort the process if one fails instead of silently ingesting the bad data and trying to sanitize random places.

Any interest in trying to address that?

--Dan