Fix Icom IC-726 mode handling.

The IC-726 doesn't accept passband width sub commands with the mode
command. Well it does for CW, but not for other modes. I have disabled
the sending passband width sub commands for this rig to at least get
the mode setting commands accepted by the rig.

Fix IC-475A/E mode set command.

As with IC-726 very limited passband width sub commands with mode set
command so disabled all for now.