[libclc] [llvm] [libclc] Enable LLVM_RUNTIME_TARGETS in build system (PR #189892)

[Joseph Huber via cfe-commits]

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@@ -147,7 +153,7 @@
     "flang": "check-flang",
     "flang-rt": "check-flang-rt",
     "libc": "check-libc",
-    "libclc": "check-libclc",
+    "libclc": "check-libclc-amdgcn-amd-amdhsa-llvm",
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jhuber6 wrote:

So, this is something that I previously proposed with @petrhosek. Right now we have the concept of the 'default' target which is the user's host triple. This is handled differently from the named ones. My thought was that the current default behavior just be treated as if someone passed `-DLLVM_RUNTIME_TARGETS=${LLVM_HOST_TRIPLE}`. Then all the `check-xyz` targets would simply depend on all the others like that. I forget if I ever made a PR for that but I don't think it went anywhere.

https://github.com/llvm/llvm-project/pull/189892