[libclc] [libclc] Reduce include usage in OpenCL builtins (PR #146840)

[Fraser Cormack via cfe-commits]

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@@ -6,5 +6,12 @@
 //
 //===----------------------------------------------------------------------===//
 
+#ifndef __CLC_OPENCL_OPENCL_INTEGER_ABS_H__
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frasercrmck wrote:

Ah it's because I copied it incorrectly from `__CLC_OPENCL_OPENCL_BASE_H__` which does need it twice. Anyway, fixed. Thanks for spotting that!

https://github.com/llvm/llvm-project/pull/146840