net: cosmetic: tftp.* checkpatch compliance

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/include/net.h b/include/net.h
index 3dbe154..92afc19 100644
--- a/include/net.h
+++ b/include/net.h
@@ -396,6 +396,10 @@
 extern int NetTimeOffset;			/* offset time from UTC */
 #endif
 
+#if defined(CONFIG_MCAST_TFTP)
+extern IPaddr_t Mcast_addr;
+#endif
+
 /* Initialize the network adapter */
 extern int NetLoop(enum proto_t);