net: ethernet: ti: am65-cpsw: use cppi5_desc_is_tdcm()

Use cppi5_desc_is_tdcm() helper for teardown indicator detection instead of
hard-coded value.
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/ti/am65-cpsw-nuss.c

@@ -767,7 +767,7 @@ static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_common *common,
 		return ret;
 	}
 
-	if (desc_dma & 0x1) {
+	if (cppi5_desc_is_tdcm(desc_dma)) {
 		dev_dbg(dev, "%s RX tdown flow: %u\n", __func__, flow_idx);
 		return 0;
 	}
@@ -935,7 +935,7 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,
 		if (res == -ENODATA)
 			break;
 
-		if (desc_dma & 0x1) {
+		if (cppi5_desc_is_tdcm(desc_dma)) {
 			if (atomic_dec_and_test(&common->tdown_cnt))
 				complete(&common->tdown_complete);
 			break;