info.py: add optional kmod modinfo section.

info.py: add optional kmod modinfo section.

The older info.py version only used comedilib to extract board
information, including the comedi version in use.  While the
out-of-kernel comedi module does bump their versions (occasionally ;),
the in-kernel staging drivers still claim version 0.7.76 (despite
being mostly equivalent to the out-of-tree module 0.10.1).  This makes
it useful to differentiate between in-kernel and out-of-kernel modules
by printing some modinfo details, for which I'm using the kmod Python
bindings (python-kmod).

I'm currently using my Cython branch of python-kmod, which is pending
a merge upstream [1].

[1]: https://github.com/agrover/python-kmod/pull/3