net: ena: enable negotiating larger Rx ring size

Use MAX_QUEUES_EXT get feature capability to query the device.

Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>