qcacmn: Fix diag_ce initialization

With more copy engines, the diag ce was not moved to the end.
The diag_ce was being assigned a null value from the unitialized
index.

Change-Id: Ib0fc6450712af2dc5e38f00bb692cfb26982ddae
CRs-Fixed: 997175

hif/src/ce/ce_main.c

@@ -1897,8 +1897,7 @@ int hif_config_ce(struct hif_softc *scn)
 		if (pipe_num == DIAG_CE_ID) {
 			/* Reserve the ultimate CE for
 			 * Diagnostic Window support */
-			hif_state->ce_diag =
-				hif_state->pipe_info[scn->ce_count - 1].ce_hdl;
+			hif_state->ce_diag = pipe_info->ce_hdl;
 			continue;
 		}