The number of lanes of devlink port should be correctly initialized
when registering the port, so that the input check when running
"devlink port split <port> count <N>" can pass.

Fixes: a21cf0a8 ("devlink: Add a new devlink port lanes attribute and pass to netlink")
Signed-off-by: Yinjun Zhang <yinjun.zhang@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>