Minor code cleanup of Klocwork issues

Minor code cleanup of Klocwork issues. Fatal messages are given no return
attribute. Define and use KMP_NORETURN to work for multiple C++ versions.

Patch by Terry Wilmarth

Differential Revision: https://reviews.llvm.org/D37275

llvm-svn: 312538
diff --git a/openmp/runtime/src/kmp_debug.cpp b/openmp/runtime/src/kmp_debug.cpp
index 6db0774..fc0cab8 100644
--- a/openmp/runtime/src/kmp_debug.cpp
+++ b/openmp/runtime/src/kmp_debug.cpp
@@ -74,8 +74,8 @@
 #endif // USE_ASSERT_SEG
 #endif
 
-  __kmp_msg(kmp_ms_fatal, KMP_MSG(AssertionFailure, file, line),
-            KMP_HNT(SubmitBugReport), __kmp_msg_null);
+  __kmp_fatal(KMP_MSG(AssertionFailure, file, line), KMP_HNT(SubmitBugReport),
+              __kmp_msg_null);
 
   return 0;