[llvm] [BOLT][NFC] Using target_triple in lit config (PR #144078)

[Amir Ayupov via llvm-commits]

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@@ -1,4 +1,4 @@
-host_linux_triple = config.target_triple.split("-")[0] + "-unknown-linux-gnu"
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aaupov wrote:

By using a linux triple regardless of the actual triple (mac, windows, ...) and passing it to clang target option below, we get ELF binaries on all platforms.

https://github.com/llvm/llvm-project/pull/144078