net: Keep the bootstage functions together

Move the bootstage_mark() function just before net_loop(), so that the
IPv6 code is not in the way.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/cmd/net.c b/cmd/net.c
index 79525f7..deebd5b 100644
--- a/cmd/net.c
+++ b/cmd/net.c
@@ -413,8 +413,6 @@
 		return CMD_RET_USAGE;
 	}
 
-	bootstage_mark(BOOTSTAGE_ID_NET_START);
-
 	if (IS_ENABLED(CONFIG_IPV6) && !use_ip6) {
 		char *s, *e;
 		size_t len;
@@ -428,6 +426,8 @@
 		}
 	}
 
+	bootstage_mark(BOOTSTAGE_ID_NET_START);
+
 	size = net_loop(proto);
 	if (size < 0) {
 		bootstage_error(BOOTSTAGE_ID_NET_NETLOOP_OK);