IB/qib: Set port physical state even if other fields are invalid

The IBTA vol. 1 release 1.2.1 spec. says:
C14-24.2.1: If PortInfo:Portstate=Down, then a SubnSet(PortInfo) shall
make any changes it specifies to PortInfo:PortPhysicalState; any other
result is vendor-dependent.

The patch changes the error handling so that the reply says there are
invalid fields but still attempts to set fields that are in range
including PortInfo:PortPhysicalState.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>