dt-bindings: display: renesas: lvds: Document r8a77995 bindings

The D3 (r8a77995) supports two LVDS channels. Extend the binding to
support them.
Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
[Fixed compatible string]
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Documentation/devicetree/bindings/display/bridge/renesas,lvds.txt

@@ -14,6 +14,7 @@ Required properties:
   - "renesas,r8a7795-lvds" for R8A7795 (R-Car H3) compatible LVDS encoders
   - "renesas,r8a7796-lvds" for R8A7796 (R-Car M3-W) compatible LVDS encoders
   - "renesas,r8a77970-lvds" for R8A77970 (R-Car V3M) compatible LVDS encoders
+  - "renesas,r8a77995-lvds" for R8A77995 (R-Car D3) compatible LVDS encoders
 
 - reg: Base address and length for the memory-mapped registers
 - clocks: A phandle + clock-specifier pair for the functional clock