[llvm] [OpenMP] Do not define '__assert_fail' if we have the GPU libc (PR #100409)

[Joseph Huber via llvm-commits]

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@@ -26,10 +26,13 @@ using namespace ompx;
 extern "C" {
 void __assert_assume(bool condition) { __builtin_assume(condition); }
 
+#ifndef OMPTARGET_HAS_LIBC
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jhuber6 wrote:

Yeah we should probably do it all at once.

https://github.com/llvm/llvm-project/pull/100409