This change allows the set_mode functions to leave the rig passband
unchanged if required. For the few rigs that do not have explcit
passband width control either current state is read and rewritten or a
"normal" width is chosen e.g. select a normal width when there is a
choice like CW and CW-NARROW.
- Ensure that all variables have a value before they are used (ft920).
- Disable unused functions and variables (frg100).
- Incremented backend version numbers.
git-svn-id: https://hamlib.svn.sourceforge.net/svnroot/hamlib/trunk@2120 7ae35d74-ebe9-4afe-98af-79ac388436b8