crypto: marvell/cesa - add DT bindings documentation

Marvell Cryptographic Engines And Security Accelerator

Required properties:

- compatible: should be one of the following string

	      "marvell,orion-crypto"

	      "marvell,kirkwood-crypto"

	      "marvell,dove-crypto"

	      "marvell,armada-370-crypto"

	      "marvell,armada-xp-crypto"

	      "marvell,armada-375-crypto"

	      "marvell,armada-38x-crypto"

- reg: base physical address of the engine and length of memory mapped

       region. Can also contain an entry for the SRAM attached to the CESA,

       but this representation is deprecated and marvell,crypto-srams should

       be used instead

- reg-names: "regs". Can contain an "sram" entry, but this representation

	     is deprecated and marvell,crypto-srams should be used instead

- interrupts: interrupt number

- clocks: reference to the crypto engines clocks. This property is not

	  required for orion and kirkwood platforms

- clock-names: "cesaX" and "cesazX", X should be replaced by the crypto engine

	       id.

	       This property is not required for the orion and kirkwoord

	       platforms.

	       "cesazX" clocks are not required on armada-370 platforms

- marvell,crypto-srams: phandle to crypto SRAM definitions

Optional properties:

- marvell,crypto-sram-size: SRAM size reserved for crypto operations, if not

			    specified the whole SRAM is used (2KB)

Examples:

	crypto@90000 {

		compatible = "marvell,armada-xp-crypto";

		reg = <0x90000 0x10000>;

		reg-names = "regs";

		interrupts = <48>, <49>;

		clocks = <&gateclk 23>, <&gateclk 23>;

		clock-names = "cesa0", "cesa1";

		marvell,crypto-srams = <&crypto_sram0>, <&crypto_sram1>;

		marvell,crypto-sram-size = <0x600>;

		status = "okay";

	};