[llvm] [llvm][docs] Correct description of %t lit substitution (PR #164397)

[Martin Storsjö via llvm-commits]

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@@ -628,7 +628,7 @@ TestRunner.py:
  %{fs-src-root}          root component of file system paths pointing to the LLVM checkout
  %{fs-tmp-root}          root component of file system paths pointing to the test's temporary directory
  %{fs-sep}               file system path separator
- %t                      temporary file name unique to the test
+ %t                      the path of a temporary file unique to the test
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mstorsjo wrote:

"the path of a temporary file" - this makes it sound like there is a file with this name that already exists - while it's just a unique path, that the test can do whatever it wants about.

https://github.com/llvm/llvm-project/pull/164397