qcacmn: Get vdev stats based on arch

With Single Netdev Unified and Hybrid Mode,
the calculation of vdev stats is changed as
per the mode. For LI platforms the path
to get vdev stats is still same while for
BE the vdev stats config path is different.
Introduced Arch ops to handle this diversion.

Change-Id: If4f0f49e78d35126942cd3f1872a5856e4d0f5ba
CRs-Fixed: 3482567

dp/wifi3.0/dp_stats.c

@@ -8661,7 +8661,7 @@ void dp_update_vdev_stats_on_peer_unmap(struct dp_vdev *vdev,
 	uint8_t link_id = 0;
 	struct dp_pdev *pdev = vdev->pdev;
 
-	if (soc && soc->arch_ops.dp_get_vdev_stats_for_unmap_peer)
+	if (soc->arch_ops.dp_get_vdev_stats_for_unmap_peer)
 		soc->arch_ops.dp_get_vdev_stats_for_unmap_peer(vdev,
 							       peer,
 							       &vdev_stats);