Fix tor-fw-helper-natpmp.c API usage

libnatpmp-20110618 changed the API that tor-fw-helper used and for a time
tor-fw-helper could not build against the newest libnatpmp. This patch brings
support for libnatpmp to tor-fw-helper.

changes/bug3434

@@ -0,0 +1,2 @@
+  o Minor bugfixes:
+    - Update tor-fw-helper to support libnatpmp-20110618; fixes 3434.

configure.in

@@ -545,7 +545,7 @@ if test "$natpmp" = "true"; then
         [   int r;
             natpmp_t natpmp;
             natpmpresp_t response;
-            r = initnatpmp(&natpmp);],
+            r = initnatpmp(&natpmp, 0, 0);],
             [printf("initnatpmp() returned %d (%s)\n", r, r?"FAILED":"SUCCESS");
             exit(0);],
         [--with-libnatpmp-dir],

src/tools/tor-fw-helper/tor-fw-helper-natpmp.c

@@ -55,7 +55,7 @@ tor_natpmp_init(tor_fw_options_t *tor_fw_options, void *backend_state)
   if (tor_fw_options->verbose)
     fprintf(stdout, "V: natpmp init...\n");
 
-  r = initnatpmp(&(state->natpmp));
+  r = initnatpmp(&(state->natpmp), 0, 0);
   if (r == 0) {
     state->init = 1;
     fprintf(stdout, "tor-fw-helper: natpmp initialized...\n");