arm64: dts: marvell: Disable AP I2C on Armada-8040-DB

arm64: dts: marvell: Disable AP I2C on Armada-8040-DB

While AP I2C bus was available to users in early revisions of the SoC,
this is not the case anymore since eMMC was connected to the AP. Most
users do not have access to this I2C bus so do not enable it in the
board device tree.

As there are three I2C buses enabled on this board, add an alias to be
sure the two other buses keep their initial numbering.

Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
[<miquel.raynal@bootlin.com>: Reword commit message, add alias]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>