[llvm] [RISCV] Add basic Mach-O triple support. (PR #141682)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,26 @@
+; RUN: llvm-mc -triple riscv32-apple-macho %s -o - | FileCheck %s
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MaskRay wrote:

Remove the `riscv-` prefix from the filename

https://github.com/llvm/llvm-project/pull/141682