If we create a kmod_module from a name, the path returned is relative to
the module dirname, as passed during kmod_ctx creation. Note that if
kmod_ctx is created with kmod_new(NULL), the dir used is the one
returned by uname.
kmod_loaded_get_list() now returns a regular list of kmod_modules, use
kmod_module_get_module(), kmod_module_unref() and
kmod_module_unref_list() to operate on it.
It doesn't run with `make check' since
o It's dangerous
o It needs to be run as root
o It needs an argument, otherwise it removes the first module
with use_count==0
