ar71xx: fix mac offset in firmware file

In new firmware-4.bin (for ath10k) mac offset is 0x114 (276), not 0x118 (280).
This also closes #19751, bug introduced in #45624

Signed-off-by: Cezary Jackiewicz <cezary.jackiewicz@gmail.com>

SVN-Revision: 45958

target/linux/ar71xx/base-files/lib/preinit/82_patch_ath10k

@@ -29,7 +29,7 @@ do_patch_ath10k_firmware() {
 
 			cp $firmware_file /tmp/ath10k-firmware.bin
 			macaddr_2bin $mac | dd of=/tmp/ath10k-firmware.bin \
-				conv=notrunc bs=1 seek=280 count=6
+				conv=notrunc bs=1 seek=276 count=6
 
 		;;
 	esac