ARM: dts: Fix I2C repeated start issue on Armada-38x

All the Armada 38x(380, 385, 388) have a silicon issue in
the I2C controller which violates the I2C repeated start timing
(errata FE-8471889).

i2c-mv64xxx driver handles this errata based on the compatible string
"marvell,mv78230-a0-i2c".

This patch activates the "marvell,mv78230-a0-i2c" compatible string
for the I2C controller on armada-38x SoC based devices.

Signed-off-by: Kalyan Kinthada <kalyan.kinthada@alliedtelesis.co.nz>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>