mac80211: optimise station flags

The flaglock in struct sta_info has long been
something that I wanted to get rid of, this
finally does the conversion to atomic bitops.

The conversion itself is straight-forward in
most places, a few things needed to change a
bit since we can no longer use multiple bits
at the same time.

On x86-64, this is a fairly significant code
size reduction:
   text	   data	    bss	    dec	    hex
 427861	  23648	   1008	 452517	  6e7a5	before
 425383	  23648	    976	 450007	  6ddd7	after

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 3cef5a7..2ac0339 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -382,7 +382,7 @@
 	    sdata->vif.type != NL80211_IFTYPE_AP)
 		return -EINVAL;
 
-	if (test_sta_flags(sta, WLAN_STA_BLOCK_BA)) {
+	if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
 #ifdef CONFIG_MAC80211_HT_DEBUG
 		printk(KERN_DEBUG "BA sessions blocked. "
 		       "Denying BA session request\n");