T3 firmware only supports one WRs worth of page list for fast register
work requests.  The driver currently allows 2 WRs worth, which
doesn't work for T3, so reduce the limit in the driver.
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>