Merge the generated has_<name> fields into a single one.

git-svn-id: https://svn.kapsi.fi/jpa/nanopb-dev@1008 e3a754e5-d11d-0410-8d38-ebb782a927b9

example/client.c

@@ -45,11 +45,11 @@ bool listdir(int fd, char *path)
     
     if (path == NULL)
     {
-        request.has_path = false;
+        ListFilesRequest_clear(request, path);
     }
     else
     {
-        request.has_path = true;
+        ListFilesRequest_set(request, path);
         if (strlen(path) + 1 > sizeof(request.path))
         {
             fprintf(stderr, "Too long path.\n");