arm64: dts: marvell: Move clocks to AP806 specific file

Regular clocks and CPU clocks are specific to AP806, move them out of
the generic AP80x file so that AP807 can use its own clocks.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>