net: ena: Don't register memory info on XDP exchange

Since the queues aren't destroyed when we only exchange XDP programs,
there's no need to re-register them again.

Fixes: 548c4940 ("net: ena: Implement XDP_TX action")
Signed-off-by: Shay Agroskin <shayagr@amazon.com>
Signed-off-by: David Arinzon <darinzon@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>