ath9k: update to DFS pattern detector interface

Follow updates in DFS pattern detector interface:
a) use given pulse event structure
b) adapt to boolean return value of add_pulse()

Signed-off-by: Zefir Kurtisi <zefir.kurtisi@neratec.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --cc drivers/net/wireless/ath/ath9k/dfs.c
Simple merge

diff --cc drivers/net/wireless/ath/ath9k/dfs.h
Simple merge