net: cosmetic: Name ethaddr variables consistently

Use "_ethaddr" at the end of variables and drop CamelCase.
Make constant values actually 'const'.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/board/tcm-bf537/tcm-bf537.c b/board/tcm-bf537/tcm-bf537.c
index a4f0f71..2531a44 100644
--- a/board/tcm-bf537/tcm-bf537.c
+++ b/board/tcm-bf537/tcm-bf537.c
@@ -31,7 +31,7 @@
 		return;
 
 	printf("Warning: %s: generating 'random' MAC address\n", var);
-	eth_random_addr(enetaddr);
+	net_random_ethaddr(enetaddr);
 	eth_setenv_enetaddr(var, enetaddr);
 }