gve: set page count for RX QPL for GQI and DQO queue formats

gve: set page count for RX QPL for GQI and DQO queue formats

Fulfill the requirement that for GQI, the number of pages per
RX QPL is equal to the ring size. Set this value to be equal to
ring size. Because of this change, the rx_data_slot_cnt and
rx_pages_per_qpl fields stored in the priv structure are not
needed, so remove their usage. And for DQO, the number of pages
per RX QPL is more than ring size to account for out-of-order
completions. So set it to two times of rx ring size.

Reviewed-by: Praveen Kaligineedi <pkaligineedi@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>