net: Fix error if some network features are disabled

If 'CONFIG_CMD_TFTPBOOT' or 'CONFIG_CMD_BOOTP' are disabled, the usage must be disabled, too!

Signed-off-by: Olaf Krebs <olaf.krebs@emh-metering.com>
CC: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/cmd/net.c b/cmd/net.c
index 25390b0..9bbcdbc 100644
--- a/cmd/net.c
+++ b/cmd/net.c
@@ -135,11 +135,15 @@
 		env_set("netmask", tmp);
 	}
 
+#ifdef CONFIG_CMD_BOOTP
 	if (net_hostname[0])
 		env_set("hostname", net_hostname);
+#endif
 
+#ifdef CONFIG_CMD_BOOTP
 	if (net_root_path[0])
 		env_set("rootpath", net_root_path);
+#endif
 
 	if (net_ip.s_addr) {
 		ip_to_string(net_ip, tmp);
@@ -165,8 +169,10 @@
 		env_set("dnsip2", tmp);
 	}
 #endif
+#ifdef CONFIG_CMD_BOOTP
 	if (net_nis_domain[0])
 		env_set("domain", net_nis_domain);
+#endif
 
 #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_TIMEOFFSET)
 	if (net_ntp_time_offset) {
diff --git a/net/net.c b/net/net.c
index 3793291..11683dd 100644
--- a/net/net.c
+++ b/net/net.c
@@ -456,6 +456,7 @@
 		net_dev_exists = 1;
 		net_boot_file_size = 0;
 		switch (protocol) {
+#ifdef CONFIG_CMD_TFTPBOOT
 		case TFTPGET:
 #ifdef CONFIG_CMD_TFTPPUT
 		case TFTPPUT:
@@ -463,6 +464,7 @@
 			/* always use ARP to get server ethernet address */
 			tftp_start(protocol);
 			break;
+#endif
 #ifdef CONFIG_CMD_TFTPSRV
 		case TFTPSRV:
 			tftp_start_server();
@@ -480,13 +482,13 @@
 			dhcp_request();		/* Basically same as BOOTP */
 			break;
 #endif
-
+#if defined(CONFIG_CMD_BOOTP)
 		case BOOTP:
 			bootp_reset();
 			net_ip.s_addr = 0;
 			bootp_request();
 			break;
-
+#endif
 #if defined(CONFIG_CMD_RARP)
 		case RARP:
 			rarp_try = 0;