[Marco Filippi iz3gme.marco@gmail.com] [FT7800] Fix TSQL-R tone mode support

I think this broke the build:

Traceback (most recent call last): File "./share/make_supported.py", line 140, in <module> if _radio.get_features().has_sub_devices: File "./chirp/vx170.py", line 129, in get_features rf = super(VX170Radio, self).get_features() File "./chirp/ft7800.py", line 297, in get_features rf.valid_tmodes = self.TMODES AttributeError: 'VX170Radio' object has no attribute 'TMODES'

I guess this didn't get hit in the test round because we don't run make_supported.

Marco, can you spin a fix?

--Dan