[clang] [clang][bytecode] Fix unknown size arrays crash in clang bytecode (PR #160015)

[Timm Baeder via cfe-commits]

================
@@ -0,0 +1,14 @@
+// Test that strlen() on external/unknown declarations doesn't crash the bytecode interpreter
----------------
tbaederr wrote:

This test doesn't do anything, check the others for appropriate RUN lines.

https://github.com/llvm/llvm-project/pull/160015