powerpc/83xx/km: add MV88E6122 switch support for kmvect1

kmvect1 has a UEC2 connection to the piggy board and a UEC0 connection
to the switch MV88E6122. This switch has a connection to a frontport
ethernet interface. The ethernet port used for network booting is
automatically selected by u-boot. If a Piggy is plugged, the Piggy
port is selected (UEC2, eth1). If the Piggy isn't present, the
Frontport is selected (UEC0, eth0).

The switch reset is connected to a GPIO on the PRIO3 board FPGA (GPIO28)
and released at startup.

Signed-off-by: Karlheinz Jerg <karlheinz.jerg@keymile.com>
Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
diff --git a/board/keymile/common/ivm.c b/board/keymile/common/ivm.c
index d568fd9..22d5256 100644
--- a/board/keymile/common/ivm.c
+++ b/board/keymile/common/ivm.c
@@ -233,7 +233,13 @@
 	if (getenv("ethaddr") == NULL)
 		setenv((char *)"ethaddr", (char *)valbuf);
 #endif
-
+#ifdef CONFIG_KMVECT1
+/* KMVECT1 has two ethernet interfaces */
+	if (getenv("eth1addr") == NULL) {
+		calculate_mac_offset(buf, valbuf, 1);
+		setenv((char *)"eth1addr", (char *)valbuf);
+	}
+#endif
 	/* IVM_MacCount */
 	count = (buf[10] << 24) +
 		   (buf[11] << 16) +