staging: wilc1000: correctly check if associatedsta has not been found

The current check for associatedsta being set to -1 to indicate it has
not been found is not working because associatedsta is initialized to
zero and will never be -1.  Fix this by initializing it to ~0 and checking
for ~0 instead.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wilc1000/wilc_wfi_cfgoperations.c

@@ -1191,7 +1191,7 @@ static int get_station(struct wiphy *wiphy, struct net_device *dev,
 	struct wilc_priv *priv;
 	struct wilc_vif *vif;
 	u32 i = 0;
-	u32 associatedsta = 0;
+	u32 associatedsta = ~0;
 	u32 inactive_time = 0;
 	priv = wiphy_priv(wiphy);
 	vif = netdev_priv(dev);
@@ -1204,7 +1204,7 @@ static int get_station(struct wiphy *wiphy, struct net_device *dev,
 			}
 		}
 
-		if (associatedsta == -1) {
+		if (associatedsta == ~0) {
 			netdev_err(dev, "sta required is not associated\n");
 			return -ENOENT;
 		}