Modules: remove unneeded release function

Now that kobjects properly clean up their name structures, no matter if
they have a release function or not, we can drop this empty module
kobject release function too (it was needed prior to this because of the
way we handled static kobject names, we based the fact that if a release
function was present, then we could safely free the name string, now we
are more smart about things and only free names we have previously set.)

Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>