dt-bindings: tas2562: Add device specification links

Add device specification links for the TAS2562 and TAS2563.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Link: https://lore.kernel.org/r/20200817172151.26564-2-dmurphy@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/tas2562.yaml

@@ -16,6 +16,10 @@ description: |
   Integrated speaker voltage and current sense provides for
   real time monitoring of loudspeaker behavior.
 
+  Specifications about the audio amplifier can be found at:
+    https://www.ti.com/lit/gpn/tas2562
+    https://www.ti.com/lit/gpn/tas2563
+
 properties:
   compatible:
     enum: