closes bpo-35025: Properly guard the `CLOCK_GETTIME` et al macros in timemodule.c. (GH-9961)

Guard the `CLOCK_GETTIME` et al macros in `timemodule` based on the availability of the parent functions
(cherry picked from commit 94451182)
Co-authored-by: Max Bélanger <aeromax@gmail.com>

Misc/NEWS.d/next/macOS/2018-10-18-23-54-55.bpo-35025.X4LFJg.rst

+Properly guard the use of the ``CLOCK_GETTIME`` et al. macros in ``timemodule``
+on macOS.

Modules/timemodule.c

@@ -1700,6 +1700,8 @@ PyInit_time(void)
     /* Set, or reset, module variables like time.timezone */
     PyInit_timezone(m);
 
+#if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_CLOCK_SETTIME) || defined(HAVE_CLOCK_GETRES)
+
 #ifdef CLOCK_REALTIME
     PyModule_AddIntMacro(m, CLOCK_REALTIME);
 #endif
@@ -1728,6 +1730,8 @@ PyInit_time(void)
     PyModule_AddIntMacro(m, CLOCK_UPTIME);
 #endif
 
+#endif  /* defined(HAVE_CLOCK_GETTIME) || defined(HAVE_CLOCK_SETTIME) || defined(HAVE_CLOCK_GETRES) */
+
     if (!initialized) {
         if (PyStructSequence_InitType2(&StructTimeType,
                                        &struct_time_type_desc) < 0)