arm64: dts: mediatek: mt7986: fix SPI nodename

BugLink: https://bugs.launchpad.net/bugs/2060097

[ Upstream commit bbe266c70e1343ee3e71ca31138141b3da265085 ]

This fixes following validation errors:
arch/arm64/boot/dts/mediatek/mt7986a-rfb.dtb: spi_nand@0: $nodename:0: 'spi_nand@0' does not match '^(flash|.*sram|nand)(@.*)?$'
        from schema $id: http://devicetree.org/schemas/mtd/spi-nand.yaml#
arch/arm64/boot/dts/mediatek/mt7986b-rfb.dtb: spi_nand@0: $nodename:0: 'spi_nand@0' does not match '^(flash|.*sram|nand)(@.*)?$'
        from schema $id: http://devicetree.org/schemas/mtd/spi-nand.yaml#

Fixes: 885e153ed7 ("arm64: dts: mt7986: add spi related device nodes")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20231116130952.5099-2-zajec5@gmail.com
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 44e3e38dabddb9a759301418c678f3124874fc4b)
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

arch/arm64/boot/dts/mediatek/mt7986a-rfb.dts

@@ -237,7 +237,8 @@
 	pinctrl-0 = <&spi_flash_pins>;
 	cs-gpios = <0>, <0>;
 	status = "okay";
-	spi_nand: spi_nand@0 {
+
+	spi_nand: flash@0 {
 		compatible = "spi-nand";
 		reg = <0>;
 		spi-max-frequency = <10000000>;

arch/arm64/boot/dts/mediatek/mt7986b-rfb.dts

@@ -152,7 +152,8 @@
 	pinctrl-0 = <&spi_flash_pins>;
 	cs-gpios = <0>, <0>;
 	status = "okay";
-	spi_nand: spi_nand@0 {
+
+	spi_nand: flash@0 {
 		compatible = "spi-nand";
 		reg = <0>;
 		spi-max-frequency = <10000000>;