assembly-llvm/riscv-redundant-memory-stores.rs hardcodes riscv64 target triple

tests/assembly-llvm/riscv-redundant-memory-stores.rs currently contains:

//@ compile-flags: -Copt-level=3 --target riscv64gc-unknown-linux-gnu

In downstream bootstrap environments such as Yocto, compiletest may already be configured with a vendor-specific RISC-V target (e.g. riscv64-poky-linux-gnu).

The hardcoded target override causes rustc to require core/std artifacts for riscv64gc-unknown-linux-gnu, which may not exist in the stage2 sysroot.

As a result, the test fails before codegen:

error[E0463]: can't find crate for std``

Other nearby assembly tests (for example riscv-float-struct-abi.rs) avoid this issue by being self-contained no_std/no_core tests.

This test appears to only validate generated RISC-V assembly and does not seem to require a specific vendor triple.

Removing the explicit --target riscv64gc-unknown-linux-gnu and relying on the compiletest-configured riscv64 target makes the test pass in this environment.

Would it make sense to avoid hardcoding the target triple here?

Start with tests/assembly-llvm/riscv-redundant-memory-stores.rs and compare its compile flags with nearby riscv-float-struct-abi.rs. Check how compiletest supplies the configured RISC-V target, then verify the assembly test no longer requests a separate target triple and passes without requiring unavailable std artifacts.