dt-bindings: mediatek: add support for mt6765 reference board

Update binding document for mt6765 reference board
Signed-off-by: Mars Cheng <mars.cheng@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/arm/mediatek.txt

@@ -11,6 +11,7 @@ compatible: Must contain one of
    "mediatek,mt6589"
    "mediatek,mt6592"
    "mediatek,mt6755"
+   "mediatek,mt6765"
    "mediatek,mt6795"
    "mediatek,mt6797"
    "mediatek,mt7622"
@@ -41,6 +42,9 @@ Supported boards:
 - Evaluation phone for MT6755(Helio P10):
     Required root node properties:
       - compatible = "mediatek,mt6755-evb", "mediatek,mt6755";
+- Evaluation board for MT6765(Helio P22):
+    Required root node properties:
+      - compatible = "mediatek,mt6765-evb", "mediatek,mt6765";
 - Evaluation board for MT6795(Helio X10):
     Required root node properties:
       - compatible = "mediatek,mt6795-evb", "mediatek,mt6795";