[libclc] [libclc] Move external-funcs.test to static file and use IR checks for .cl tests (PR #197151)

[Wenju He via cfe-commits]

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@@ -0,0 +1,14 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 6
+// REQUIRES: AMDGCN
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wenju-he wrote:

> Can this stick with the usual amdgpu-registered-target like llvm?

done

https://github.com/llvm/llvm-project/pull/197151