Staging: wlan-ng: Use !x instead of x == NULL.

Use !x instead of x == NULL.
This issue was found by checkpatch.
Signed-off-by: Sandhya Bankar <bankarsandhya512@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wlan-ng/cfg80211.c

@@ -265,7 +265,7 @@ static int prism2_get_station(struct wiphy *wiphy, struct net_device *dev,
 
 	memset(sinfo, 0, sizeof(*sinfo));
 
-	if ((wlandev == NULL) || (wlandev->msdstate != WLAN_MSD_RUNNING))
+	if (!wlandev || (wlandev->msdstate != WLAN_MSD_RUNNING))
 		return -EOPNOTSUPP;
 
 	/* build request message */
@@ -274,7 +274,7 @@ static int prism2_get_station(struct wiphy *wiphy, struct net_device *dev,
 	quality.dbm.status = P80211ENUM_msgitem_status_data_ok;
 
 	/* send message to nsd */
-	if (wlandev->mlmerequest == NULL)
+	if (!wlandev->mlmerequest)
 		return -EOPNOTSUPP;
 
 	result = wlandev->mlmerequest(wlandev, (struct p80211msg *)&quality);