libkmod: Avoid redundant kmod_pool_get_module call

libkmod: Avoid redundant kmod_pool_get_module call

Before kmod_module_new_from_path creates a module with kmod_module_new,
it checks with kmod_pool_get_module if a module with given name already
exists.

This check can be removed, because kmod_module_new does the same. If the
module already existed, the same checks are performed as in current code
for the "if (m != NULL)" case. If it did not exist yet, m->path is NULL
and the first if-block is entered.

And since kmod_module_new takes care of incrementing the reference
counter, the explicit call of kmod_module_ref can be removed from
kmod_module_new_from_path as well.

Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://github.com/kmod-project/kmod/pull/168
Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>