[llvm] Add target-byteorder for cases where endian in target triple is what matters (PR #107915)

[Eli Friedman via llvm-commits]

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@@ -364,6 +364,13 @@ def version_int(ver):
     config.available_features.add("llvm-64-bits")
 
 config.available_features.add("host-byteorder-" + sys.byteorder + "-endian")
+if re.match(
+    r"(aarch64_be|arc|armeb|bpfeb|lanai|m68k|mips|mips64|powerpc|powerpc64|sparc|sparcv9|s390x|s390|tce|thumbeb)-.*",
+    config.target_triple,
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efriedma-quic wrote:

Maybe stick this check under the `if config.target_triple:`?

https://github.com/llvm/llvm-project/pull/107915