wl1271: Implement delayed entry into ELP

Implement delayed entry into ELP. This will promote the following:
 - Less redundant sleep/wake cycles (better perf)
 - Avoids known firmware issues with going to ELP too fast after an
   operation

Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Reviewed-by: Vidhya Govindan <vidhya.govindan@nokia.com>
Signed-off-by: Luciano Coelho <luciano.coelho@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/wl12xx/wl1271.h b/drivers/net/wireless/wl12xx/wl1271.h
index e575dcc..c455dcb 100644
--- a/drivers/net/wireless/wl12xx/wl1271.h
+++ b/drivers/net/wireless/wl12xx/wl1271.h
@@ -373,6 +373,7 @@
 	bool elp;
 
 	struct completion *elp_compl;
+	struct delayed_work elp_work;
 
 	/* we can be in psm, but not in elp, we have to differentiate */
 	bool psm;