If a device is already a macvlan port then refuse to use it as
an ipvlan port in the early stage of port creation.
thost1:~# ip link add link eth0 mvl0 type macvlan
thost1:~# echo $?
0
thost1:~# ip link add link eth0 ipvl0 type ipvlan
RTNETLINK answers: Device or resource busy
thost1:~# echo $?
2
thost1:~#
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
764e433b3c