dt-bindings: mtd: nand-chip: Reference mtd.yaml

A NAND chip is an MTD device. mtd.yaml already defines many useful and
relevant properties, let's reference this file here to get access to
these additional property definitions.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20221114090315.848208-4-miquel.raynal@bootlin.com

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

@@ -9,6 +9,9 @@ title: NAND Chip and NAND Controller Generic Binding
 maintainers:
   - Miquel Raynal <miquel.raynal@bootlin.com>
 
+allOf:
+  - $ref: "mtd.yaml#"
+
 description: |
   This file covers the generic description of a NAND chip. It implies that the
   bus interface should not be taken into account: both raw NAND devices and