rarp: Condtionally compile rarp support

Most people don't use the 'rarpboot' command, so only enable it when
CONFIG_CMD_RARP is defined.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
diff --git a/common/cmd_net.c b/common/cmd_net.c
index 3ffb9df..44d17db 100644
--- a/common/cmd_net.c
+++ b/common/cmd_net.c
@@ -54,6 +54,7 @@
 	"[loadAddress] [[hostIPaddr:]bootfilename]"
 );
 
+#ifdef CONFIG_CMD_RARP
 int do_rarpb (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	return netboot_common (RARP, cmdtp, argc, argv);
@@ -64,6 +65,7 @@
 	"boot image via network using RARP/TFTP protocol",
 	"[loadAddress] [[hostIPaddr:]bootfilename]"
 );
+#endif
 
 #if defined(CONFIG_CMD_DHCP)
 int do_dhcp (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])