regulator: dt-bindings: Revise the rt5190a buck/ldo description

Revise the rt5190a bucks and ldo property description.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
Link: https://lore.kernel.org/r/1650610255-6180-1-git-send-email-u0084500@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: ChiYuan Huang

Documentation/devicetree/bindings/regulator/richtek,rt5190a-regulator.yaml

@@ -58,7 +58,7 @@ properties:
         type: object
         $ref: regulator.yaml#
         description: |
-          regulator description for buck1 and buck4.
+          regulator description for buck1 to buck4, and ldo.
 
         properties:
           regulator-allowed-modes: