An Extended Port Info packet is sent to each hw port during HCA init.
If it returns without error, we assume the port supports extended port
capabilities.
Signed-off-by: Marcel Apfelbaum <marcela@dev.mellanox.co.il> Reviewed-by: Jack Morgenstein <jackm@dev.mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>