[llvm] [libsycl] Add lit configuration files and basic test (PR #177407)

[Kseniya Tikhomirova via llvm-commits]

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@@ -0,0 +1,214 @@
+# -*- Python -*-
+
+# Configuration file for the 'lit' test runner.
+
+import os
+import re
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KseniyaTikhomirova wrote:

llvm CI has python script formatting check (by graphite) but unused "import" was not reported so it seems this check doesn't exist there.

https://github.com/llvm/llvm-project/pull/177407