samples: net: wifi: Enable NXP_WIFI_TX_RX_ZERO_COPY for IW610

Enable NXP_WIFI_TX_RX_ZERO_COPY for IW610, which will reduce extra memcpy
between net stack and driver in TX data path and avoid the allocation of
RXPD and mlan_buffer in RX data path, to improve the throughput
performance.
Increase CONFIG_NET_BUF_DATA_SIZE to hold one packet in one buffer.
NXP_WIFI_TX_RX_ZERO_COPY can be enabled not only for NXP_RW610 case.

Signed-off-by: Maochen Wang <maochen.wang@nxp.com>