mac80211: switch to ieee80211_sdata_running

Since the introduction of ieee80211_sdata_running(),
some new code was introduced that uses netif_running()
instead. Switch all these instances over.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --cc net/mac80211/cfg.c
Simple merge

diff --cc net/mac80211/main.c
Simple merge

diff --cc net/mac80211/util.c
Simple merge