dt-bindings: ap80x: replace AP806 with AP80x

Rename the text file and update "AP806" into "AP806/AP807" where
relevant.
Signed-off-by: Ben Peled <bpeled@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>

Documentation/devicetree/bindings/arm/marvell/ap806-system-controller.txt → Documentation/devicetree/bindings/arm/marvell/ap80x-system-controller.txt

-Marvell Armada AP806 System Controller
+Marvell Armada AP80x System Controller
 ======================================
 
-The AP806 is one of the two core HW blocks of the Marvell Armada 7K/8K
-SoCs. It contains system controllers, which provide several registers
-giving access to numerous features: clocks, pin-muxing and many other
-SoC configuration items. This DT binding allows to describe these
-system controllers.
+The AP806/AP807 is one of the two core HW blocks of the Marvell Armada
+7K/8K/931x SoCs. It contains system controllers, which provide several
+registers giving access to numerous features: clocks, pin-muxing and
+many other SoC configuration items. This DT binding allows to describe
+these system controllers.
 
 For the top level node:
  - compatible: must be: "syscon", "simple-mfd";
- - reg: register area of the AP806 system controller
+ - reg: register area of the AP80x system controller
 
 SYSTEM CONTROLLER 0
 ===================