wlan: Update the Channel Change Reason

Update the channel change reason to the default generic channel switch
reason before initiating channel switch.
If this is not done, the channel change reason in "0" which is
LIM_SWITCH_CHANNEL_REASSOC  and is leading to a reassociation.

Change-Id: I09d676a9f17b37d8fc16aff7759be5fe4277e9ce
CR-Fixed: 384996
diff --git a/CORE/MAC/src/pe/lim/limUtils.c b/CORE/MAC/src/pe/lim/limUtils.c
index c371236..be1bbe4 100644
--- a/CORE/MAC/src/pe/lim/limUtils.c
+++ b/CORE/MAC/src/pe/lim/limUtils.c
@@ -5584,6 +5584,9 @@
                                  "nel Offset: %d, Channel Width: %d\n" ),
                 pHTInfo->primaryChannel, secondaryChnlOffset,
                 psessionEntry->htRecommendedTxWidthSet );
+        psessionEntry->channelChangeReasonCode=LIM_SWITCH_CHANNEL_OPERATION;
+        pMac->lim.gpchangeChannelCallback = NULL;
+        pMac->lim.gpchangeChannelData = NULL;
 
 #if defined WLAN_FEATURE_VOWIFI  
         limSendSwitchChnlParams( pMac, ( tANI_U8 ) pHTInfo->primaryChannel,