gnuradio: remove host-python-cheetah dependency

host-python-cheetah has been replaced by host-python-mako:
https://github.com/gnuradio/volk/commit/1b2bedc8685c4dc2b3587068339d69b5ab1c874d



Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>