IB/qib: Avoid filtering LID on SMA portinfo

The current get portinfo handling filters the LID being sent,
changing zero to 0xffff.

This causes OpenSM to log excessive warning messages.

Reviewed-by: Edward Mascarenhas <edward.mascarenhas@qlogic.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>