Traditional SLI4 required the driver to clear Valid bits on
EQEs and CQEs after consuming them.

The new if_type=6 hardware will cycle the value for what is
valid on each queue itteration. The driver no longer has to
touch the valid bits. This also means all the cpu cache
dirtying and perhaps flush/refill's done by the hardware
in accessing the EQ/CQ elements is eliminated.
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>