co_help_gtk wasn't built

src/tools/pwre/src/os_linux/pwre.pl

@@ -605,6 +605,7 @@ sub build_all ()
     }
     if ( $exe == 1) {
       _build("exe", "rt*", "src", "all");
+      _build("exe", "co*", $flavour, "all");
       _build("exe", "pwr_user", "src", "all");
       _build("exe", "pwr_rtmon", "src", "all");
       _build("exp", "ge", "src", "all");