[clang] [-Wunterminated-string-initialization] Handle C string literals ending with explicit '\0' (PR #143487)

[Yanzuo Liu via cfe-commits]

================
@@ -0,0 +1,28 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -Wunterminated-string-initialization %s -x c
+// RUN: %clang_cc1 -fsyntax-only -verify -Wunterminated-string-initialization %s -x c++
+
+
+// In C, the following examples are fine:
+#if __cplusplus
----------------
zwuis wrote:

```suggestion
#ifdef __cplusplus
```


https://github.com/llvm/llvm-project/pull/143487