VxWorks: fixup MAC address for VxWorks

VxWorks 7 kernels retrieve 'local-mac-addr' from dtb and use
that for NIC MAC address. As a result, when booting the same
kernel image on multiple boards, there will be address
conflicts.

So fixup MAC address when booting VxWorks 7 kernels

Signed-off-by: Miao Yan <yanmiaobest@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/common/bootm_os.c b/common/bootm_os.c
index 72477f0..cb83f4a 100644
--- a/common/bootm_os.c
+++ b/common/bootm_os.c
@@ -288,6 +288,8 @@
 		if (ret)
 			return;
 
+		fdt_fixup_ethernet(*of_flat_tree);
+
 		ret = fdt_add_subnode(*of_flat_tree, 0, "chosen");
 		if ((ret >= 0 || ret == -FDT_ERR_EXISTS)) {
 			bootline = getenv("bootargs");