rename pa_hook_free() to pa_hook_done() since the hook struct is allocated on the stack not via malloc

src/tests/hook-list-test.c

@@ -31,7 +31,7 @@ int main(int argc, char *argv[]) {
 
     pa_hook_fire(&hook, (void*) "call2");
 
-    pa_hook_free(&hook);
+    pa_hook_done(&hook);
 
     return 0;
 }