This increases the amount of bundling to reduce the number of packets
sent.  For the one wire use there can be multiple struct
w1_netlink_cmd in a struct w1_netlink_msg and multiple of those in
struct cn_msg, and with this change multiple of those in a struct
nlmsghdr, and at each level the len identifies there being multiple of
the next.
Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>