mediatek: fix gmac definition for cudy m3000

The gmac definition has an offset of 1 compared to the label MAC.
Fixes: a55ab9e ("mediatek: filogic: prevent faulty mac address assignment")

Signed-off-by: Maximilian Baumgartner <aufhaxer@googlemail.com>
Link: openwrt#21560
Signed-off-by: Robert Marko <robimarko@gmail.com>

Author: mbaumga

target/linux/mediatek/dts/mt7981b-cudy-m3000-v1.dts

@@ -86,7 +86,7 @@
 		phy-handle = <&rtl8221b_phy>;
 
 		nvmem-cell-names = "mac-address";
-		nvmem-cells = <&macaddr_bdinfo_de00 1>;
+		nvmem-cells = <&macaddr_bdinfo_de00 0>;
 	};
 
 	gmac1: mac@1 {
@@ -96,7 +96,7 @@
 		phy-handle = <&int_gbe_phy>;
 
 		nvmem-cell-names = "mac-address";
-		nvmem-cells = <&macaddr_bdinfo_de00 0>;
+		nvmem-cells = <&macaddr_bdinfo_de00 1>;
 	};
 };