rndis_wlan: make some variables unsigned

These variables can never be less than zero because we cap them in
get_device_pmkids().  Let's make them unsigned here because it's simpler
to not have to worry about negative numbers when we read the code.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rndis_wlan.c

@@ -1790,7 +1790,8 @@ static struct ndis_80211_pmkid *remove_pmkid(struct usbnet *usbdev,
 						struct cfg80211_pmksa *pmksa,
 						int max_pmkids)
 {
-	int i, count, newlen, err;
+	int i, newlen, err;
+	unsigned int count;
 
 	count = le32_to_cpu(pmkids->bssid_info_count);
 
@@ -1830,7 +1831,8 @@ static struct ndis_80211_pmkid *update_pmkid(struct usbnet *usbdev,
 						struct cfg80211_pmksa *pmksa,
 						int max_pmkids)
 {
-	int i, err, count, newlen;
+	int i, err, newlen;
+	unsigned int count;
 
 	count = le32_to_cpu(pmkids->bssid_info_count);