spi: nuvoton,npcm-fiu: Change spi-nor@0 name to flash@0

The node name for flash memories has been standardized to "flash@...".
Fix the example in nuvoton,npcm-fiu.txt accordingly.

Signed-off-by: Jonathan Neuschäfer <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

Documentation/devicetree/bindings/spi/nuvoton,npcm-fiu.txt

···
 	clocks = <&clk NPCM7XX_CLK_AHB>;
 	pinctrl-names = "default";
 	pinctrl-0 = <&spi3_pins>;
-	spi-nor@0 {
+	flash@0 {
 			...
 	};
 };