Add some "3.9" attributes to srcs in gnuradio packages And update
packages using GR3.8 and that are incompatible yet with GR3.9 to use
GR3.8 explicitly.
- Write a `mkDerivation` and `mkDerivationWith` function for gnuradio,
like qt5.
- qradiolink, gqrx: Use gnuradio's callPackage and mkDerivation.
- Use gnuradio.callPackage to define all gnuradio.pkgs.
- Move all gnuradio packages expressions to pkgs/development/gnuradio-modules/ -
modeled after Python's.
- Add more paths to gnuradio's wrapper - add the extra packages as
python modules, and add their executables with proper env vars
wrapping.
Co-authored-by: Frederik Rietdijk <fridh@fridh.nl>
