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/net/dns.c b/net/dns.c
index 6f8b1f2..0ff2b75 100644
--- a/net/dns.c
+++ b/net/dns.c
@@ -89,7 +89,7 @@
 
 	DnsOurPort = random_port();
 
-	NetSendUDPPacket(NetServerEther, net_dns_server, DNS_SERVICE_PORT,
+	NetSendUDPPacket(net_server_ethaddr, net_dns_server, DNS_SERVICE_PORT,
 			 DnsOurPort, n);
 	debug("DNS packet sent\n");
 }
@@ -203,7 +203,7 @@
 	net_set_udp_handler(dns_handler);
 
 	/* Clear a previous MAC address, the server IP might have changed. */
-	memset(NetServerEther, 0, sizeof(NetServerEther));
+	memset(net_server_ethaddr, 0, sizeof(net_server_ethaddr));
 
 	DnsSend();
 }