[llvm] [LIT] replace `lit.util.mkdir` with `pathlib.Path.mkdir` (PR #163948)

[Alexander Richardson via llvm-commits]

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@@ -462,16 +462,15 @@ def executeBuiltinMkdir(cmd, cmd_shenv):
     stderr = StringIO()
     exitCode = 0
     for dir in args:
-        cwd = cmd_shenv.cwd
-        dir = to_unicode(dir) if kIsWindows else to_bytes(dir)
-        cwd = to_unicode(cwd) if kIsWindows else to_bytes(cwd)
-        if not os.path.isabs(dir):
-            dir = lit.util.abs_path_preserve_drive(os.path.join(cwd, dir))
+        dir = pathlib.Path(dir)
+        cwd = pathlib.Path(to_unicode(cmd_shenv.cwd))
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arichardson wrote:

All these python2->3 to_unicode() etc. helpers should probably be cleaned up as a follow-up.

https://github.com/llvm/llvm-project/pull/163948