CONTRIB: debug: fix build related to conn_stream flags change

Commit 53216e7db ("MEDIUM: connections: Don't directly mess with the
polling from the upper layers.") removed the CS_FL_DATA_RD_ENA and
CS_FL_DATA_WR_ENA flags without updating flags.c, thus breaking the
build. This patch also adds flag CL_FL_NOT_FIRST which was brought
by commit 08088e77c.
diff --git a/contrib/debug/flags.c b/contrib/debug/flags.c
index ae885d6..545e6c2 100644
--- a/contrib/debug/flags.c
+++ b/contrib/debug/flags.c
@@ -156,6 +156,7 @@
 		printf("0\n");
 		return;
 	}
+	SHOW_FLAG(f, CS_FL_NOT_FIRST);
 	SHOW_FLAG(f, CS_FL_WAIT_FOR_HS);
 	SHOW_FLAG(f, CS_FL_REOS);
 	SHOW_FLAG(f, CS_FL_EOS);
@@ -165,8 +166,6 @@
 	SHOW_FLAG(f, CS_FL_SHWN);
 	SHOW_FLAG(f, CS_FL_SHRR);
 	SHOW_FLAG(f, CS_FL_SHRD);
-	SHOW_FLAG(f, CS_FL_DATA_WR_ENA);
-	SHOW_FLAG(f, CS_FL_DATA_RD_ENA);
 
 	if (f) {
 		printf("EXTRA(0x%08x)", f);