dbug/dbug_analyze.c : Avoid the unresolved symbol "my_thread_global_init()"

                        in a build "--without-server".

Fix for bug#14685


dbug/dbug_analyze.c:
  In a build "--without-server", the libraries will be built without threading.
  In this case, "my_thread_global_init()" is missing in the libraries, and the 
  linker will report an unresolved symbol.
  
  Avoid this error by making the call to "my_thread_global_init()" depend on 
  "#ifdef THREAD".
  
  Fix for bug#14685

dbug/dbug_analyze.c

@@ -574,10 +574,12 @@ int main (int argc, char **argv)
     FILE *infile;
     FILE *outfile = {stdout};
 
-#if defined(HAVE_PTHREAD_INIT) && defined(THREAD)
+#ifdef THREAD
+#if defined(HAVE_PTHREAD_INIT)
   pthread_init();                       /* Must be called before DBUG_ENTER */
 #endif
   my_thread_global_init();
+#endif /* THREAD */
   {
     DBUG_ENTER ("main");
     DBUG_PROCESS (argv[0]);