
Adjust #89280: * ELFOSABI_LINUX is a historical alias that should not be used in new code. readelf -h displays "UNIX - GNU" instead of "Linux". * "OS" is inappropriate. Some values are architecture-specific, e.g. ELFOSABI_ARM. * Drop lowercase, which seems a job of the caller. Add some unittests. Pull Request: https://github.com/llvm/llvm-project/pull/90270