mac80211: A couple of fixes to dynamic power save.

a) hw_config() should not be called from siwpower() for the drivers which do not support
   dynamic powersave.
b) IEEE80211_HW_NO_STACK_DYNAMIC_PS needs to be verified in set_associated() also before
   enabling the power save timers.

Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index b688425..b3c99d3 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -751,7 +751,8 @@
 	bss_info_changed |= BSS_CHANGED_BASIC_RATES;
 	ieee80211_bss_info_change_notify(sdata, bss_info_changed);
 
-	if (local->powersave) {
+	if (local->powersave &&
+			!(local->hw.flags & IEEE80211_HW_NO_STACK_DYNAMIC_PS)) {
 		if (local->dynamic_ps_timeout > 0)
 			mod_timer(&local->dynamic_ps_timer, jiffies +
 				  msecs_to_jiffies(local->dynamic_ps_timeout));