[llvm] [DTLTO] Added missing timetrace "Check cache for DTLTO" message. (PR #203215)

[Ben Dunbobbin via llvm-commits]

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@@ -9,12 +9,15 @@ RUN: opt -thinlto-bc t2.ll -o t2.bc
 ; Generate fake object files for mock.py to return.
 RUN: touch t1.o t2.o
 
+RUN: rm -rf %t.cache && mkdir -p %t.cache
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bd1976bris wrote:

```suggestion
RUN: mkdir cache
```
then later on `--cache-dir=%t.cache \` -> `--cache-dir=cache \`

https://github.com/llvm/llvm-project/pull/203215