dt-bindings: arm: amazon: add missing alpine-v2 DT binding

Amazon Annapurna Labs Alpine family includes: Alpine-v1, Alpine-v2.

This patch adds the missing DT binding of Alpine-v2 in amazon,al.yaml.

Link: https://lore.kernel.org/r/20200724132654.16549-5-hhhawa@amazon.com
Signed-off-by: Hanna Hawa <hhhawa@amazon.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Documentation/devicetree/bindings/arm/amazon,al.yaml

@@ -13,10 +13,15 @@ maintainers:
 
 properties:
   compatible:
-    items:
-      - const: al,alpine
-  model:
-    items:
-      - const: "Annapurna Labs Alpine Dev Board"
+    oneOf:
+      - description: Boards with Alpine V1 SoC
+        items:
+          - const: al,alpine
+
+      - description: Boards with Alpine V2 SoC
+        items:
+          - enum:
+              - al,alpine-v2-evp
+          - const: al,alpine-v2
 
 ...