ASoC: rt1016: Add the devicetree file for the rt1016

The patch adds the devicetree file for the rt1016.
Signed-off-by: NOder Chiou <oder_chiou@realtek.com>
Link: https://lore.kernel.org/r/20200507021539.7133-2-oder_chiou@realtek.comSigned-off-by: NMark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/rt1016.txt

+RT1016 Stereo Class D Audio Amplifier
+
+This device supports I2C only.
+
+Required properties:
+
+- compatible : "realtek,rt1016".
+
+- reg : The I2C address of the device.
+
+
+Example:
+
+rt1016: codec@1a {
+	compatible = "realtek,rt1016";
+	reg = <0x1a>;
+};