Add ath9k eeprom and pci fixup support (again) for linux 3.7.

On linux 3.3, the fixup forced the regdomain to 0x67, causing low TX power.
This patch only corrects checksum, the rest of the EEPROM isn't changed.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@35353 3c298f89-4303-0410-b956-a3cf2f4a3e73