bootvx: get mac address from environment

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
CC: Niklaus Giger <niklaus.giger@member.fsf.org>
CC: Ben Warren <biggerbadderben@gmail.com>
diff --git a/common/cmd_elf.c b/common/cmd_elf.c
index 19e1249..4a3fff1 100644
--- a/common/cmd_elf.c
+++ b/common/cmd_elf.c
@@ -131,10 +131,12 @@
 
 #if defined(CONFIG_WALNUT)
 	tmp = (char *) CONFIG_SYS_NVRAM_BASE_ADDR + 0x500;
-	memcpy ((char *) tmp, (char *) &gd->bd->bi_enetaddr[3], 3);
+	eth_getenv_enetaddr("ethaddr", build_buf);
+	memcpy(tmp, &build_buf[3], 3);
 #elif defined(CONFIG_SYS_VXWORKS_MAC_PTR)
 	tmp = (char *) CONFIG_SYS_VXWORKS_MAC_PTR;
-	memcpy ((char *) tmp, (char *) &gd->bd->bi_enetaddr[0], 6);
+	eth_getenv_enetaddr("ethaddr", build_buf);
+	memcpy(tmp, build_buf, 6);
 #else
 	puts ("## Ethernet MAC address not copied to NV RAM\n");
 #endif