dt-bindings: arm: mediatek: Add MT8195 Cherry Tomato Chromebooks

Document board compatibles for the MT8195 Cherry platform's
Tomato Chromebooks, at the time of writing composed of four
revisions (r1, r2, r3-r4).

Signed-off-by: AngeloGioacchino Del Regno <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Matthias Brugger <[e-mail]>

Documentation/devicetree/bindings/arm/mediatek.yaml

···
           - const: google,spherion-rev0
           - const: google,spherion
           - const: mediatek,mt8192
+      - description: Acer Tomato (Acer Chromebook Spin 513 CP513-2H)
+        items:
+          - enum:
+              - google,tomato-rev2
+              - google,tomato-rev1
+          - const: google,tomato
+          - const: mediatek,mt8195
+      - description: Acer Tomato rev3 - 4 (Acer Chromebook Spin 513 CP513-2H)
+        items:
+          - const: google,tomato-rev4
+          - const: google,tomato-rev3
+          - const: google,tomato
+          - const: mediatek,mt8195
       - items:
           - enum:
               - mediatek,mt8186-evb