feat: Add riscv64 support

[ffgan]

Hi there.

Recently, riscv64 (rv64) has gained widespread adoption, and we might consider adding rv64 support to sccache. Our build image messense/rust-musl-cross has excellent support for rv64, so we can easily add rv64 support to sccache, but there are two points that need special mention.

One of our dependencies is openssl. The version we currently use fails to compile on rv64, so we need to upgrade the version.

I chose to upgrade to the latest version, 300.5.4+3.5.4, which compiles successfully for non-s390x architectures. For s390x, there's a compilation issue: Error: Unrecognized opcode: 'cijne'. After reviewing related issues, I inserted a compilation flag specifically for s390x to enable it to compile successfully. For the specific code, please refer to the content in the PR.

The patch comes from two sources: 1, 2.

No other modifications are needed to complete the compilation. I ran CI in my fork, and the results show everything is good. Please check the links below for details:

1. ci
2. integration-tests

Regarding the ci, there are some failed jobs that I need to briefly explain. Some failures are due to running in my fork and lacking token, which causes Upload coverage results to fail—this doesn't affect this PR. Others are due to The macOS-13 based runner images are now retired, which also doesn't affect this PR.

Therefore, we can add rv64 support very well.

If you have any questions about the above content, please @ me directly. I'm happy to answer all questions.

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Other Info
Co-authored by: [email protected];

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 66.97%. Comparing base (6e4aafe) to head (43f06dd).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2512   +/-   ##
=======================================
  Coverage   66.97%   66.97%           
=======================================
  Files          64       64           
  Lines       35359    35359           
=======================================
+ Hits        23681    23683    +2     
+ Misses      11678    11676    -2     

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[ffgan]

Hi @sylvestre . Thank you for merging this PR. Could we please consider releasing a new version so that we can directly use sccache for riscv64?