[llvm] [RISCV] Support .option (no)autocompress (PR #122483)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,70 @@
+# RUN: llvm-mc -triple riscv32 -show-encoding -mattr=+c < %s \
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MaskRay wrote:

llvm-mc doesn't need `< `

https://github.com/llvm/llvm-project/pull/122483