staging: fsl-dpaa2/eth: Fix SGT allocation

We mistakenly allocate space for too many entries in the
scatter-gather table of multi buffer egress frames.

While it doesn't have a negative impact from a functional
point of view, it wastes resources so fix it.
Signed-off-by: Ioana Radulescu <ruxandra.radulescu@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fsl-dpaa2/ethernet/dpaa2-eth.c

@@ -373,7 +373,7 @@ static int build_sg_fd(struct dpaa2_eth_priv *priv,
 
 	/* Prepare the HW SGT structure */
 	sgt_buf_size = priv->tx_data_offset +
-		       sizeof(struct dpaa2_sg_entry) * (1 + num_dma_bufs);
+		       sizeof(struct dpaa2_sg_entry) *  num_dma_bufs;
 	sgt_buf = netdev_alloc_frag(sgt_buf_size + DPAA2_ETH_TX_BUF_ALIGN);
 	if (unlikely(!sgt_buf)) {
 		err = -ENOMEM;