net/octeontx: fix packet corruption on Tx

net/octeontx: fix packet corruption on Tx

LMTST does not guarantee packet content get synced with L2C when
HW access the packet for transmitting.

Adding coherent IO write barrier will make sure HW sees the correct
packet if its modified.

Fixes: 9e747589bd4c ("net/octeontx: add packet transmit burst function")
Cc: stable@dpdk.org
Reported-by: Vikas Aggarwal <vikas.aggarwal@caviumnetworks.com>
Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Santosh Shukla <santosh.shukla@caviumnetworks.com>