qcacld-3.0: Fix exception in hdd_get_station_statistics_cb()

An exception was observed in hdd_get_station_statistics_cb() when
validating the pStatsContext.  The speculation is that the caller had
already timed out, and the act of dereferencing the pStatsContext
caused an exception even though the context was on the caller's stack.
To fix this issue move the context from the stack to the BSS.

Change-Id: Ib7adf158e04b174bdf5745491b6787bc2e27d610
CRs-Fixed: 1086276

core/hdd/src/wlan_hdd_wext.c

@@ -3789,7 +3789,7 @@ QDF_STATUS wlan_hdd_get_station_stats(hdd_adapter_t *pAdapter)
 	hdd_station_ctx_t *pHddStaCtx = WLAN_HDD_GET_STATION_CTX_PTR(pAdapter);
 	QDF_STATUS hstatus;
 	unsigned long rc;
-	struct statsContext context;
+	static struct statsContext context;
 
 	if (NULL == pAdapter) {
 		hdd_err("pAdapter is NULL");