Set IO Sync Barrier flags for all Mbus devices on Armada38x
IO Sync Barrier setting is required for I/O coherency.
Reviewed by: andrew, ian, imp
Obtained from: Semihalf
Sponsored by: Stormshield
Submitted by: Michal Stanek <mst@semihalf.com>
Differential revision: https://reviews.freebsd.org/D4219