ath9k: Set default noise floor value for AR9287

The default noise floor was never initialized for
AR9287.This patch helps in reporting the correct
RSSI for this version of chipset.

Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2 files changed