davinci_emac: hardcode 100Mbps for AM35xx and RMII

For some reason code setting the speed based on the PHY feedback causes
troubles on AM3517 so hardcode 100Mbps for now.

Signed-off-by: Ilya Yanok <yanok@emcraft.com>
diff --git a/drivers/net/davinci_emac.c b/drivers/net/davinci_emac.c
index 4760390..d6c4e63 100644
--- a/drivers/net/davinci_emac.c
+++ b/drivers/net/davinci_emac.c
@@ -520,7 +520,8 @@
 	writel(1, &adap_emac->RXUNICASTSET);
 
 	/* Enable MII interface and Full duplex mode */
-#ifdef CONFIG_SOC_DA8XX
+#if defined(CONFIG_SOC_DA8XX) || \
+	(defined(CONFIG_OMAP34XX) && defined(CONFIG_DRIVER_TI_EMAC_USE_RMII))
 	writel((EMAC_MACCONTROL_MIIEN_ENABLE |
 		EMAC_MACCONTROL_FULLDUPLEX_ENABLE |
 		EMAC_MACCONTROL_RMIISPEED_100),