8139cp: Fix one possible deadloop in cp_rx_poll

When cp_rx_poll does not get enough packet, it will check the rx
interrupt status again. If so, it will jumpt to rx_status_loop again.
But the goto jump resets the rx variable as zero too.

As a result, it causes one possible deadloop. Assume this case,
rx_status_loop only gets the packet count which is less than budget,
and (cpr16(IntrStatus) & cp_rx_intr_mask) condition is always true.
It causes the deadloop happens and system is blocked.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/8139cp.c

@@ -467,8 +467,8 @@ static int cp_rx_poll(struct napi_struct *napi, int budget)
 	unsigned int rx_tail = cp->rx_tail;
 	int rx;
 
-rx_status_loop:
 	rx = 0;
+rx_status_loop:
 	cpw16(IntrStatus, cp_rx_intr_mask);
 
 	while (rx < budget) {