dt-bindings: mtd: gpmi-nand: ref to nand-controller-legacy.yaml

Ref to nand-controller-legacy.yaml instead nand-controller.yaml to allow
legacy DT layout.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Author: nxpfrankli

Documentation/devicetree/bindings/mtd/gpmi-nand.yaml

@@ -101,7 +101,7 @@ required:
 unevaluatedProperties: false
 
 allOf:
-  - $ref: nand-controller.yaml
+  - $ref: nand-controller-legacy.yaml
 
   - if:
       properties: