REORG: include: move port_range.h to haproxy/port_range{,-t}.h

The port ranges didn't depend on anything. However they were missing
some includes such as stdlib and api-t.h which were added.
diff --git a/src/checks.c b/src/checks.c
index cd1649b..499bc51 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -57,7 +57,7 @@
 #include <proto/log.h>
 #include <proto/mux_pt.h>
 #include <proto/queue.h>
-#include <proto/port_range.h>
+#include <haproxy/port_range.h>
 #include <proto/proto_tcp.h>
 #include <haproxy/protocol.h>
 #include <proto/proxy.h>