BUILD: stats: Missing headers inclusions from stats.h

If we add a new stats module to C source files including only
stats.h we get these errors:

    include/haproxy/stats.h:39:31: error: array type has incomplete element type
    ‘struct name_desc’
       39 | extern const struct name_desc stat_fields[];

    include/haproxy/stats.h:55:50: warning: ‘struct listener’ declared inside
    parameter list will not be visible outside of this definition or declaration
       55 | int stats_fill_li_stats(struct proxy *px, struct listener *l, int flags,

name_desc struct is defined in tools-t.h and listener struct in listner-t.h.

include/haproxy/stats.h

@@ -24,7 +24,9 @@
 #define _HAPROXY_STATS_H
 
 #include <haproxy/api.h>
+#include <haproxy/listener-t.h>
 #include <haproxy/stats-t.h>
+#include <haproxy/tools-t.h>
 
 struct channel;
 struct buffer;