staging: lustre: move misc-device registration closer to related code.

The ioctl handler for the misc device is in  lnet/libcfs/module.c
but is it registered in lnet/libcfs/linux/linux-module.c.

Keeping related code together make maintenance easier, so move the
code.

Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>