cpmac: wait longer after MDIO reset

This patch slows down the MDIO_ALIVE busy waiting to let
switches and PHY come up after reset. Previous loop was
too quick for IC+175C and ADM6996C/L switches to come up.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/cpmac.c b/drivers/net/cpmac.c
index 7b311c6..645e644 100644
--- a/drivers/net/cpmac.c
+++ b/drivers/net/cpmac.c
@@ -1245,11 +1245,11 @@
 
 	cpmac_mii->reset(cpmac_mii);
 
-	for (i = 0; i < 300000; i++)
+	for (i = 0; i < 300; i++)
 		if ((mask = cpmac_read(cpmac_mii->priv, CPMAC_MDIO_ALIVE)))
 			break;
 		else
-			cpu_relax();
+			msleep(10);
 
 	mask &= 0x7fffffff;
 	if (mask & (mask - 1)) {