ath9k_hw: Fix INI fixup

Commit "ath9k_hw: move AR9280 PCI EEPROM fix to eeprom_def.c"
changed the behavior of INI overriding which is needed only
for PCI cards. Revert to the original check.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>