qcacmn: Fix compilation error

There's no declaration for API dp_peer_qos_stats_notify().
Define the API  as "static inline".

Change-Id: Id6769d680b3304cebf00b2348fb5b9a3bc9c7368
CRs-Fixed: 2773655

dp/wifi3.0/dp_internal.h

@@ -1746,8 +1746,9 @@ static inline QDF_STATUS dp_peer_stats_notify(struct dp_pdev *pdev,
 	return QDF_STATUS_SUCCESS;
 }
 
-QDF_STATUS dp_peer_qos_stats_notify(struct dp_pdev *dp_pdev,
-				    struct cdp_rx_stats_ppdu_user *ppdu_user)
+static inline QDF_STATUS
+dp_peer_qos_stats_notify(struct dp_pdev *dp_pdev,
+			 struct cdp_rx_stats_ppdu_user *ppdu_user)
 {
 	return QDF_STATUS_SUCCESS;
 }