ath9k_hw: simplify revision checks for AR9287

Since AR9287 v1.0 was never sold (and the initvals removed), its revision
checks can be simplified similar to AR9280

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
5 files changed