pthread_cond_timedwait on zOS returns EAGAIN,  not ETIMEDOUT as on other unix platforms.
Change apr_thread_cond_timedwait to check platform and rv when deciding to return APR_TIMEUP.
I didn't add any config for the zOS rv , as it didn't seem to add anything.

apr/testall testlock  test_timeoutcond will pass with this change, it does not currently.

Index: thread_cond.c
--- thread_cond.c       (revision 579232)
+++ thread_cond.c       (working copy)
@@ -92,7 +92,11 @@
         rv = errno;
+#ifdef __MVS__
+    if (EAGAIN == rv) {
     if (ETIMEDOUT == rv) {
+#endif /* __MVS__ */
         return APR_TIMEUP;
     return rv;