dt-bindings: mips: loongson: Add LS1B-DEMO and CQ-T300B

Document two Loongson-1 boards:
 - loongson,ls1b-demo: a board based on Loongson-1B
 - loongson,cq-t300b: a board based on Loongson-1C

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Author: kelvincheung

Documentation/devicetree/bindings/mips/loongson/devices.yaml

@@ -40,13 +40,15 @@ properties:
       - description: LS1B based boards
         items:
           - enum:
+              - loongson,ls1b-demo
               - loongson,lsgz-1b-dev
           - const: loongson,ls1b
 
       - description: LS1C based boards
         items:
           - enum:
               - loongmasses,smartloong-1c
+              - loongson,cq-t300b
           - const: loongson,ls1c
 
 additionalProperties: true