ANDROID: clean up merge issues with gmu.yaml patch

The commit "FROMLIST: dt-bindings: display: msm: Convert GMU bindings to
YAML" was not quite merged the same way upstream.  So clean up our local
version to match what upstream ended up taking.

Cc: Jordan Crouse <jcrouse@codeaurora.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: https://lore.kernel.org/lkml/1582223216-23459-2-git-send-email-jcrouse@codeaurora.org/
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I5598d6deae27a1f2ec21b27a3ff6113cbcdd996b

Documentation/devicetree/bindings/display/msm/gmu.yaml

@@ -72,16 +72,9 @@ properties:
        - const: gx
 
   iommus:
-    $ref: /schemas/types.yaml#/definitions/phandle-array
-    description:
-       Phandle to a IOMMU device and stream ID. Refer to ../../iommu/iommu.txt
-       for more information.
+    maxItems: 1
 
-  operating-points-v2:
-    $ref: /schemas/types.yaml#/definitions/phandle
-    description:
-      Phandle to the OPP table for the available GMU frequencies. Refer to
-      ../../opp/opp.txt for more information.
+  operating-points-v2: true
 
   dma-ranges:
     $ref: /schemas/types.yaml#/definitions/uint32-array