net/memif: fix multi-process Tx
net/memif: fix multi-process Tx

When working as a secondary process, it uses eth_memif_rx in PMD egress.
It should be eth_memif_tx.

Fixes: c41a04958b ("net/memif: support multi-process")

Signed-off-by: Phil Yang <5a9b6465c065ff0e1fd5d2cb9eb2185e82f34247@arm.com>
Reviewed-by: Gavin Hu <207ee22c2cf71e20c5b5df8395050c07c07d8709@arm.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk