switchdev: skip over ports returning -EOPNOTSUPP when recursing ports

This allows us to recurse over all the ports, skipping over unsupporting
ports.  Without the change, the recursion would stop at first unsupported
port.

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>