ath9k: fix eeprom INI values override for 2GHz-only cards

Among other changes, this commit:

   commit 06d0f066
   Author: Sujith <Sujith.Manoharan@atheros.com>
   Date:   Thu Feb 12 10:06:45 2009 +0530

   ath9k: Enable Fractional N mode

changed the hw attach code to fix up initialization values only for
dual band devices, however the commit message did not give a reason as
to why this would be useful or necessary.

According to tests by Jorge Boncompte, this breaks at least some
2GHz-only cards, so the code should be changed back to the
unconditional INI fixup.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Reported-by: Jorge Boncompte <jorge@dti2.net>
Cc: stable@kernel.org
Tested-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>