qed: Read per queue coalesce from hardware

Retrieve the actual coalesce value from hardware for every Rx/Tx
queue, instead of Rx/Tx coalesce value cached during set coalesce.

Signed-off-by: Rahul Verma <Rahul.Verma@cavium.com>
Signed-off-by: Yuval Mintz <yuval.mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>