ARM: dts: am335x-sancloud-bbe: fix phy mode

The phy mode should be rgmii-id.  For some reason, it used to work with
rgmii-txid but doesn't any more.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am335x-sancloud-bbe.dts

@@ -108,7 +108,7 @@ ethphy0: ethernet-phy@0 {
 
 &cpsw_emac0 {
 	phy-handle = <&ethphy0>;
-	phy-mode = "rgmii-txid";
+	phy-mode = "rgmii-id";
 };
 
 &i2c0 {