gianfar: Don't needlessly set the wrap bit for the last RX BD

startup_gfar() sets the wrap bit for the last rxbd just after
gfar_new_rxbdp() call, which is issued for all rxbds. And
gfar_new_rxbdp() has the following check already:

	if (bdp == priv->rx_bd_base + priv->rx_ring_size - 1)
		lstatus |= BD_LFLAG(RXBD_WRAP);

So we don't need to set the bit again.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>