[llvm] Fix `DEBUGLOG_WITH_STREAM_TYPE_AND_FILE` broken in #150750 (PR #150920)

[Mehdi Amini via llvm-commits]

https://github.com/joker-eph approved this pull request.

Thanks!
We don't exercise this code path upstream right now.

What about adding this diff to your PR:

```
diff --git a/llvm/unittests/Support/DebugLogTest.cpp b/llvm/unittests/Support/DebugLogTest.cpp
index 8356ae856be2..3c82376734b9 100644
--- a/llvm/unittests/Support/DebugLogTest.cpp
+++ b/llvm/unittests/Support/DebugLogTest.cpp
@@ -6,6 +6,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// This macro is defined in the LLVM build system, but we undefine it here
+// so that we test at least once in-tree the case where __SHORT_FILE__ is not
+// defined.
+#undef __SHORT_FILE__
+
 #include "llvm/Support/DebugLog.h"
 #include "llvm/ADT/Sequence.h"
 #include "llvm/Support/raw_ostream.h"
```

https://github.com/llvm/llvm-project/pull/150920