[media] devicetree: bindings: Document Renesas R-Car JPEG Processing Unit

Add Renesas R-Car JPEG processing unit driver device tree bindings
documentation.
Signed-off-by: NMikhail Ulyanov <mikhail.ulyanov@cogentembedded.com>
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@osg.samsung.com>

Documentation/devicetree/bindings/media/renesas,jpu.txt

+* Renesas JPEG Processing Unit
+
+The JPEG processing unit (JPU) incorporates the JPEG codec with an encoding
+and decoding function conforming to the JPEG baseline process, so that the JPU
+can encode image data and decode JPEG data quickly.
+
+Required properties:
+  - compatible: should containg one of the following:
+			- "renesas,jpu-r8a7790" for R-Car H2
+			- "renesas,jpu-r8a7791" for R-Car M2-W
+			- "renesas,jpu-r8a7792" for R-Car V2H
+			- "renesas,jpu-r8a7793" for R-Car M2-N
+
+  - reg: Base address and length of the registers block for the JPU.
+  - interrupts: JPU interrupt specifier.
+  - clocks: A phandle + clock-specifier pair for the JPU functional clock.
+
+Example: R8A7790 (R-Car H2) JPU node
+	jpeg-codec@fe980000 {
+		compatible = "renesas,jpu-r8a7790";
+		reg = <0 0xfe980000 0 0x10300>;
+		interrupts = <0 272 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp1_clks R8A7790_CLK_JPU>;
+	};