kmp_gsupport: Fix library initialization with taskgroup

Differential Revision: https://reviews.llvm.org/D23259

llvm-svn: 278003
diff --git a/openmp/runtime/src/kmp_gsupport.c b/openmp/runtime/src/kmp_gsupport.c
index 23c97d1..62baa2b 100644
--- a/openmp/runtime/src/kmp_gsupport.c
+++ b/openmp/runtime/src/kmp_gsupport.c
@@ -1259,7 +1259,7 @@
 void
 xexpand(KMP_API_NAME_GOMP_TASKGROUP_START)(void)
 {
-    int gtid = __kmp_get_gtid();
+    int gtid = __kmp_entry_gtid();
     MKLOC(loc, "GOMP_taskgroup_start");
     KA_TRACE(20, ("GOMP_taskgroup_start: T#%d\n", gtid));