dt-bindings: leds: bd72720: Add BD72720

Add the ROHM BD72720 documentation to the binding documents.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/b9854f77ee1dca8c99a9a9a198b79fbc76f8da67.1765804226.git.mazziesaccount@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>

Author: M-Vaittinen

Documentation/devicetree/bindings/leds/rohm,bd71828-leds.yaml

@@ -10,11 +10,12 @@ maintainers:
   - Matti Vaittinen <mazziesaccount@gmail.com>
 
 description: |
-  This module is part of the ROHM BD71828 MFD device. For more details
-  see Documentation/devicetree/bindings/mfd/rohm,bd71828-pmic.yaml.
+  This module is part of the ROHM BD71828 and BD72720 MFD device. For more
+  details see Documentation/devicetree/bindings/mfd/rohm,bd71828-pmic.yaml
+  and Documentation/devicetree/bindings/mfd/rohm,bd72720-pmic.yaml
 
   The LED controller is represented as a sub-node of the PMIC node on the device
-  tree.
+  tree. This should be located under "leds" - node in PMIC node.
 
   The device has two LED outputs referred as GRNLED and AMBLED in data-sheet.