clk: mvebu: ap806-cpu: prepare mapping of AP807 CPU clock

clk: mvebu: ap806-cpu: prepare mapping of AP807 CPU clock

This patch allows same flow to be executed on chips with different
register mappings like AP806 and, in the future, AP807.

Note: this patch has no functional effect, and only prepares the
driver for additional chips to be supported by retrieving the right
device data depenging on the compatible property.

Signed-off-by: Christine Gharzuzi <chrisg@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lkml.kernel.org/r/20190805100310.29048-4-miquel.raynal@bootlin.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>