qed: Don't over-do producer cleanup for Rx

Before requesting the firmware to start Rx queues,
driver goes and sets the queue producer in the device to 0.
But while the producer is 32-bit, the driver currently clears 64 bits,
effectively zeroing an additional CID's producer as well.

Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>