Document wakeup-source property. This fixes dtbs_check warnings
when building current Linux DTs:
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arch/arm/boot/dts/stm32mp153c-dhcom-drc02.dtb: i2c@40015000: Unevaluated properties are not allowed ('wakeup-source' was unexpected)
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Signed-off-by: Marek Vasut <[email protected]>
Acked-by: Rob Herring <[email protected]>
Signed-off-by: Wolfram Sang <[email protected]>