Don't run the initialize test if we cannot stop it with a signal.

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@33784 72102866-910b-0410-8b05-ffd578937521

Tests/base/NSObject/initialize.m

@@ -118,6 +118,8 @@ int main(void)
    */
   signal(SIGALRM, alarmed);
   alarm(5);
+#else
+  SKIP("+initialize runs concurrently");
 #endif
 
   l = [NSCondition new];