dt-bindings: crypto: Convert brcm,spum-crypto to DT schema

Convert the Broadcom SPUM/SPU2 binding to DT schema format. It's a
straight forward conversion.

Signed-off-by: Rob Herring (Arm) <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

Documentation/devicetree/bindings/crypto/brcm,spu-crypto.txt

···
-The Broadcom Secure Processing Unit (SPU) hardware supports symmetric
-cryptographic offload for Broadcom SoCs. A SoC may have multiple SPU hardware
-blocks.
-
-Required properties:
-- compatible: Should be one of the following:
-  brcm,spum-crypto - for devices with SPU-M hardware
-  brcm,spu2-crypto - for devices with SPU2 hardware
-  brcm,spu2-v2-crypto - for devices with enhanced SPU2 hardware features like SHA3
-  and Rabin Fingerprint support
-  brcm,spum-nsp-crypto - for the Northstar Plus variant of the SPU-M hardware
-
-- reg: Should contain SPU registers location and length.
-- mboxes: The mailbox channel to be used to communicate with the SPU.
-  Mailbox channels correspond to DMA rings on the device.
-
-Example:
-	crypto@612d0000 {
-		compatible = "brcm,spum-crypto";
-		reg = <0 0x612d0000 0 0x900>;
-		mboxes = <&pdc0 0>;
-	};

Documentation/devicetree/bindings/crypto/brcm,spum-crypto.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/brcm,spum-crypto.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom SPU Crypto Offload
+
+maintainers:
+  - Rob Rice <[e-mail]>
+
+description:
+  The Broadcom Secure Processing Unit (SPU) hardware supports symmetric
+  cryptographic offload for Broadcom SoCs. A SoC may have multiple SPU hardware
+  blocks.
+
+properties:
+  compatible:
+    enum:
+      - brcm,spum-crypto
+      - brcm,spu2-crypto
+      - brcm,spu2-v2-crypto     # enhanced SPU2 hardware features like SHA3 and Rabin Fingerprint support
+      - brcm,spum-nsp-crypto    # Northstar Plus variant of the SPU-M hardware
+
+  reg:
+    maxItems: 1
+
+  mboxes:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - mboxes
+
+additionalProperties: false
+
+examples:
+  - |
+    crypto@612d0000 {
+        compatible = "brcm,spum-crypto";
+        reg = <0x612d0000 0x900>;
+        mboxes = <&pdc0 0>;
+    };