[dpdk-stable] 17.11.10 fails to build from source on arm64

[Christian Ehrhardt]

Hi,
17.11.10 contains:
  [1] 4cd784b0 "net/mlx5: fix Rx CQ doorbell synchronization on aarch64"
Which is a backport from 94a24aaf

But if you build on arm64 with MLX5 enabled that breaks like:
  mlx5_rxtx_vec_neon.h:1035: undefined reference to `rte_cio_wmb'

I found and confirmed that adding the following on top of 17.11.10 fixes
the issue
  [2] 52bd60a5 "eal/arm64: define coherent I/O memory barriers"

[1]:
https://git.dpdk.org/dpdk-stable/commit/?id=4cd784b02d29f706ff2297b6f65eeb680c0af9ff
[2]: https://git.dpdk.org/dpdk/commit/?id=52bd60a5

-- 
Christian Ehrhardt
Staff Engineer, Ubuntu Server
Canonical Ltd