Fix assert message.  NFC.

llvm-svn: 289657
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index 6aa34b4..3098d07 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -10808,7 +10808,7 @@
                                               SourceLocation EndLoc) {
   MappableVarListInfo MVLI(VarList);
   for (auto &RefExpr : VarList) {
-    assert(RefExpr && "NULL expr in OpenMP use_device_ptr clause.");
+    assert(RefExpr && "NULL expr in OpenMP is_device_ptr clause.");
     SourceLocation ELoc;
     SourceRange ERange;
     Expr *SimpleRefExpr = RefExpr;