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

[Fangrui Song 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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MaskRay wrote:

> BTW the reason for the patch is that `-unknown-linux-gnu` is not compatible with all linux distros.

There is not sufficient information, so I am guesting what might be happening.
Clang installation doesn't usually ship libc++ and libc, so it often requires libstdc++ and glibc on a Linux system when you don't specify -nostdlib/-nostdinc.
(Note: the linux-gnu triple we use cannot be used on a linux-musl system)

Many tests don't use -nostdlib -nostdinc, therefore with a libstdc++/glibc dependency. Ideally most tests should have -nostdlib/-nostdinc, and those that don't have a `REQUIRES:` so that they can be skipped when the Linux distro doesn't provide the files.

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