MAINTAINERS: rectify entry for MESON NAND controller bindings

Commit fbc00b5e ("dt-bindings: nand: meson: convert txt to yaml")
converts amlogic,meson-nand.txt to yaml, but misses to adjust its reference
in MAINTAINERS.

Hence, ./scripts/get_maintainer.pl --self-test=patterns complains about a
broken reference.

Repair this file reference in MESON NAND CONTROLLER DRIVER FOR AMLOGIC
SOCS.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220929123431.23180-1-lukas.bulwahn@gmail.com

MAINTAINERS

@@ -13376,7 +13376,7 @@ MESON NAND CONTROLLER DRIVER FOR AMLOGIC SOCS
 M:	Liang Yang <liang.yang@amlogic.com>
 L:	linux-mtd@lists.infradead.org
 S:	Maintained
-F:	Documentation/devicetree/bindings/mtd/amlogic,meson-nand.txt
+F:	Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml
 F:	drivers/mtd/nand/raw/meson_*
 
 MESON VIDEO DECODER DRIVER FOR AMLOGIC SOCS