wlan: Update the TDLS cfg80211 interface for 3.18 support

These two interfaces have been changed since Kernel 3.15.
And also some params passing from cfg80211 are constified.
So make the corresponding change to adapt to the interface change.

    - wlan_hdd_cfg80211_tdls_mgmt
    - wlan_hdd_cfg80211_tdls_oper

Change-Id: Ic175b5e50f84c56be78875d1b5e3a616cc65a741
CRs-fixed: 882885
diff --git a/CORE/HDD/inc/wlan_hdd_cfg80211.h b/CORE/HDD/inc/wlan_hdd_cfg80211.h
index 93e0931..524bce3 100644
--- a/CORE/HDD/inc/wlan_hdd_cfg80211.h
+++ b/CORE/HDD/inc/wlan_hdd_cfg80211.h
@@ -920,7 +920,7 @@
 
 #ifdef FEATURE_WLAN_WAPI
 void wlan_hdd_cfg80211_set_key_wapi(hdd_adapter_t* pAdapter,
-              u8 key_index, const u8 *mac_addr, u8 *key , int key_Len);
+              u8 key_index, const u8 *mac_addr, const u8 *key , int key_Len);
 #endif
 struct wiphy *wlan_hdd_cfg80211_wiphy_alloc(int priv_size);