[][Add factory label in mt7986 dts files]

[Description]
Add factory label in mt7986 dts files to make wifi driver able
to parse Factory partition with standard of_get_property() API.

[Release-log]
N/A

Change-Id: Ib5780bda3e25bfd645e930a1d5b45ffbca48ea22
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/4615428
diff --git a/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7986a-mt7975-ax6000-rfb1.dts b/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7986a-mt7975-ax6000-rfb1.dts
index f6f8cbc..cbd9c6e 100644
--- a/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7986a-mt7975-ax6000-rfb1.dts
+++ b/target/linux/mediatek/files-5.4/arch/arm64/boot/dts/mediatek/mt7986a-mt7975-ax6000-rfb1.dts
@@ -4,3 +4,8 @@
 	model = "MediaTek MT7986a RFB";
 	compatible = "mediatek,mt7986a-rfb";
 };
+
+&wbsys {
+	mediatek,mtd-eeprom = <&factory 0x0000>;
+	status = "okay";
+};