net/mlx5e: remove napi_hash_del() calls

Calling napi_hash_del() after netif_napi_del() is pointless.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>