[clang] [llvm] [llvm] Add triples for managarm (PR #87845)

[Fangrui Song via cfe-commits]

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@@ -2562,7 +2566,10 @@ void Generic_GCC::GCCInstallationDetector::AddDefaultGCCPrefixes(
   static const char *const RISCV64LibDirs[] = {"/lib64", "/lib"};
   static const char *const RISCV64Triples[] = {"riscv64-unknown-linux-gnu",
                                                "riscv64-linux-gnu",
-                                               "riscv64-unknown-elf"};
+                                               "riscv64-unknown-elf",
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MaskRay wrote:

L2449 has a comment that we should not add new elements.

The existing ones should be cleaned up as well.

https://github.com/llvm/llvm-project/pull/87845