ramips: fix MTD EEPROM offset for TL-WR840N v5

The previous offset was invalid and pointed to the end of the partition,
which was causing issues with mt76

Signed-off-by: Felix Fietkau <nbd@nbd.name>

target/linux/ramips/dts/TL-WR840NV5.dts

@@ -96,7 +96,7 @@
 &wmac {
 	status = "okay";
 	mtd-mac-address = <&factory 0xf100>;
-	mediatek,mtd-eeprom = <&factory 0x10000>;
+	mediatek,mtd-eeprom = <&factory 0x0>;
 };
 
 &ethernet {