Riscv32 clang port

[francisco-merino-quintauris]

PR checklist

• Updated function header with a short description and version number
• Added test case for bug fix or new feature
• Validated on real hardware

[jserv]

Recently, the GNU toolchain port for RISC-V 32-bit landed, with #490 and #492 merged. Given that Clang generally aims for GNU compatibility, I am wondering whether it is still necessary to maintain a separate Clang port for the RISC-V 32-bit architecture.

Would it be possible instead to standardize on the directory ports/risc-v32/gnu and introduce Clang-specific adjustments within the existing files, rather than maintaining a parallel port?

[fdesbiens]

@jserv All those contributions have been made independently by third parties.

As a first step, I was planning to merge this as is. Then, I would work with the core team to refactor things if possible. The goal is to accept the contributions and then investigate whether Clang's compatibility is good enough to avoid a distinct port.

@akifejaz, @cypherbridge and @billlamiework: feel free to chime in.