dt-bindings: usb: mtk-xhci: support property usb2-lpm-disable

Add support common property usb2-lpm-disable
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1617181553-3503-1-git-send-email-chunfeng.yun@mediatek.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml

@@ -104,6 +104,8 @@ properties:
     description: supports USB3.0 LPM
     type: boolean
 
+  usb2-lpm-disable: true
+
   imod-interval-ns:
     description:
       Interrupt moderation interval value, it is 8 times as much as that