patch 9.0.1450: MacOS: building fails if clock_gettime() is not available

Problem:    MacOS: building fails if clock_gettime() is not available.
Solution:   Add a configure check for clock_gettime(). (closes #12242)
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 29206b9a..5c10f1e 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -6146,7 +6146,7 @@
 #endif
 		},
 	{"prof_nsec",
-#ifdef HAVE_TIMER_CREATE
+#ifdef PROF_NSEC
 		1
 #else
 		0