dt-bindings: tas2770: Mark ti,asi-format to deprecated

Mark the property ti,asi-format to deprecated as it is no longer
supported.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Link: https://lore.kernel.org/r/20200924142641.12355-1-dmurphy@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/tas2770.yaml

@@ -44,6 +44,7 @@ properties:
     description: TDM TX voltage sense time slot.
 
   ti,asi-format:
+    deprecated: true
     $ref: /schemas/types.yaml#/definitions/uint32
     description: Sets TDM RX capture edge.
     enum: