wlan: More checkpatch fixes for WLAN prima driver

This patch has fixes for the following checkpatch issues:
1 ERROR: Use of strchr is deprecated: use strnchr instead.
2 WARNING: simple_strtol is obsolete, use kstrtol instead
3 WARNING: simple_strtoul is obsolete, use kstrtoul instead

Change-Id: Ib75b587f60fa8bd950d31da8ece5b8a575e66953
CR-Fixed: NA
diff --git a/CORE/HDD/src/wlan_hdd_main.c b/CORE/HDD/src/wlan_hdd_main.c
index a2274d5..4fc75bb 100644
--- a/CORE/HDD/src/wlan_hdd_main.c
+++ b/CORE/HDD/src/wlan_hdd_main.c
@@ -1171,7 +1171,7 @@
 
    if( rtnl_lock_held )
    {
-      if (strchr(pWlanDev->name, '%')) {
+     if (strnchr(pWlanDev->name, strlen(pWlanDev->name), '%')) {
          if( dev_alloc_name(pWlanDev, pWlanDev->name) < 0 )
          {
             hddLog(VOS_TRACE_LEVEL_ERROR,"%s:Failed:dev_alloc_name",__func__);