[PATCH] DM9000 - minor code cleanups

Ensure the driver's module owner field is
initialised for when this is being built and
loaded as a module.

Also change make the dm9000_tx_done function
static, as it is not exported elsewhere.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>