Synchronize invert flag order with manpages

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/extensions/libxt_dccp.c b/extensions/libxt_dccp.c
index c368ba4..8aa3d06 100644
--- a/extensions/libxt_dccp.c
+++ b/extensions/libxt_dccp.c
@@ -36,9 +36,9 @@
 {
 	printf(
 "dccp match options\n"
-" --source-port [!] port[:port]                          match source port(s)\n"
+"[!] --source-port port[:port]                          match source port(s)\n"
 " --sport ...\n"
-" --destination-port [!] port[:port]                     match destination port(s)\n"
+"[!] --destination-port port[:port]                     match destination port(s)\n"
 " --dport ...\n");
 }