IB/qib: Use rdmavt pkey verbs function

Remove qib query pkey function which is no longer needed as this is now
being done in rdmavt. The allocation and maintenance of the list still
resides in the driver.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>