Remove a bunch of lingering g_thread_init()

After this patch, there is but one remaining use of g_thread_init(),
which is in tests/slice-threadinit.c, a testcase dedicated to testing
the functionality of gslice across a g_thread_init() boundary.

This testcase is pretty meaningless these days... probably we should
delete it.

tests/asyncqueue-test.c

@@ -185,8 +185,6 @@ main (int argc, char *argv[])
   gint   sort_interval;
   gchar *msg G_GNUC_UNUSED;
 
-  g_thread_init (NULL);
-
   basic_tests ();
 
   PRINT_MSG (("creating async queue..."));

tests/child-test.c

@@ -164,9 +164,6 @@ main (int argc, char *argv[])
     }
 #endif
 
-#ifdef TEST_THREAD
-  g_thread_init (NULL);
-#endif
   main_loop = g_main_loop_new (NULL, FALSE);
 
 #ifdef G_OS_WIN32

tests/gobject/performance-threaded.c

@@ -357,9 +357,6 @@ main (int   argc,
       return 0;
     }
 
-  if (n_threads)
-    g_thread_init (NULL);
-
   if (argc > 1)
     {
       for (i = 1; i < argc; i++)

tests/mainloop-test.c

@@ -404,8 +404,6 @@ main (int   argc,
 {
   gint i;
 
-  g_thread_init (NULL);
-
   context_array = g_ptr_array_new ();
 
   crawler_array = g_ptr_array_new ();

tests/onceinit.c

@@ -124,8 +124,6 @@ main (int   argc,
   g_assert (p == &dummy_value);
   p = initializer2();
   g_assert (p == &dummy_value);
-  /* setup threads */
-  g_thread_init (NULL);
   /* start multiple threads for initializer3() */
   g_mutex_lock (&tmutex);
   for (i = 0; i < N_THREADS; i++)

tests/slice-test.c

@@ -264,8 +264,6 @@ main (int   argc,
       seedp = &seed32;
     }
 
-  g_thread_init (NULL);
-
   if (argc <= 1)
     usage();
 

tests/thread-test.c

@@ -382,7 +382,6 @@ int
 main (int   argc,
       char *argv[])
 {
-  g_thread_init (NULL);
   run_all_tests ();
 
   /* Now we rerun all tests, but this time we fool the system into

tests/threadpool-test.c

@@ -452,8 +452,6 @@ test_check_start_and_stop (gpointer user_data)
 int
 main (int argc, char *argv[])
 {
-  g_thread_init (NULL);
-
   DEBUG_MSG (("Starting... (in one second)"));
   g_timeout_add (1000, test_check_start_and_stop, NULL);