wlan: Send proper reason code for deauth frame.

Currently during del_sta if CFG80211_DEL_STA_V2 flag is
not defined, internal reason code eCsrForcedDeauthSta is
populated and this reason code is finally send over the air.
As a part of fix made sure that proper reason code is send
over the air.

Change-Id: I2b7e2c37cd7ac268e26b89231b9af5248bfba050
CRs-Fixed: 775581
diff --git a/CORE/HDD/src/wlan_hdd_main.c b/CORE/HDD/src/wlan_hdd_main.c
index af7a751..a8315eb 100644
--- a/CORE/HDD/src/wlan_hdd_main.c
+++ b/CORE/HDD/src/wlan_hdd_main.c
@@ -10169,7 +10169,8 @@
 
                 WLANSAP_PopulateDelStaParams(
                             pSapCtx->aStaInfo[i].macAddrSTA.bytes,
-                            eCsrForcedDeauthSta, SIR_MAC_MGMT_DEAUTH >> 4,
+                            eSIR_MAC_DEAUTH_LEAVING_BSS_REASON,
+                            SIR_MAC_MGMT_DEAUTH >> 4,
                             &delStaParams);
                 vos_status = hdd_softap_sta_deauth(pAdapter, &delStaParams);
                 if (VOS_IS_STATUS_SUCCESS(vos_status))