dt-bindings: display: simple-bridge: Add corpro,gm7123 compatible

The corpro,gm7123 was in use in a DT but was never properly documented,
let's add it.

Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210721140424.725744-12-maxime@cerno.tech

Documentation/devicetree/bindings/display/bridge/simple-bridge.yaml

@@ -22,6 +22,9 @@ properties:
               - ti,ths8134a
               - ti,ths8134b
           - const: ti,ths8134
+      - items:
+          - const: corpro,gm7123
+          - const: adi,adv7123
       - enum:
           - adi,adv7123
           - dumb-vga-dac