prism54: Convert stats_sem in a mutex

The semaphore stats_sem is used as mutex, convert it to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Acked-by: Luis R. Rodriguez <mcgrof@winlab.rutgers.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/prism54/islpci_dev.h b/drivers/net/wireless/prism54/islpci_dev.h
index b03a2ab..85ddf89 100644
--- a/drivers/net/wireless/prism54/islpci_dev.h
+++ b/drivers/net/wireless/prism54/islpci_dev.h
@@ -88,7 +88,7 @@
 
 	/* Take care of the wireless stats */
 	struct work_struct stats_work;
-	struct semaphore stats_sem;
+	struct mutex stats_lock;
 	/* remember when we last updated the stats */
 	unsigned long stats_timestamp;
 	/* The first is accessed under semaphore locking.