Note that we skip lz4/brotli/zstd tests on RISC-V.
The CI runs RISC-V tests using cross/QEMU emulation. The decompression
tools (lz4, brotli, zstd) are x86_64 binaries on the host that cannot
execute in the RISC-V QEMU environment.
Skip these three tests at compile-time on RISC-V to avoid test failures.
The -z/--search-zip functionality itself works correctly on real RISC-V
hardware where native decompression tools are available.
PR #3165
7c2161d687