dt-bindings: arm: l2x0: Tauros 3 is PL310 compatible

The validation is unhappy about mmp3-dell-ariel declaring its
marvell,tauros3-cache node to be compatible with arm,pl310-cache:

  mmp3-dell-ariel.dt.yaml: cache-controller@d0020000: compatible:
       Additional items are not allowed ('arm,pl310-cache' was unexpected)
  mmp3-dell-ariel.dt.yaml: cache-controller@d0020000: compatible:
       ['marvell,tauros3-cache', 'arm,pl310-cache'] is too long

Let's allow this -- Tauros 3 is designed to be compatible with PL310.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
[robh: fixup indentation]
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/arm/l2c2x0.yaml

@@ -29,7 +29,8 @@ allOf:
 
 properties:
   compatible:
-    enum:
+    oneOf:
+      - enum:
           - arm,pl310-cache
           - arm,l220-cache
           - arm,l210-cache
@@ -47,9 +48,11 @@ properties:
             # Marvell Controller designed to be
             # compatible with the ARM one with outer cache mode.
           - marvell,aurora-outer-cache
+      - items:
            # Marvell Tauros3 cache controller, compatible
            # with arm,pl310-cache controller.
-      - marvell,tauros3-cache
+          - const: marvell,tauros3-cache
+          - const: arm,pl310-cache
 
   cache-level:
     const: 2