wlan: fix format specifier in logs

This is to remove the compiler warnings on a 64 bit machine. use a
generic specifier like %zu instead of %d to print size_t

Change-Id: I3a10365ea62639f5e5897e6d6f3f56a8c30db1cf
CRs-Fixed: 639770
diff --git a/CORE/HDD/src/wlan_hdd_cfg80211.c b/CORE/HDD/src/wlan_hdd_cfg80211.c
index 1d58977..19df165 100644
--- a/CORE/HDD/src/wlan_hdd_cfg80211.c
+++ b/CORE/HDD/src/wlan_hdd_cfg80211.c
@@ -5343,7 +5343,7 @@
                 else
                 {
                     hddLog(VOS_TRACE_LEVEL_ERROR, "Scan Ie length is invalid:"
-                             "%d", request->ie_len);
+                             "%zu", request->ie_len);
                 }
 
             }