`blst` fails to build in Windows on ARM device about blst

[dot-asm]

Oh! The first aarch64-pc-windows-msvc user! Ever! :-)

Specifically the referred failure is arguably a cc-rs bug, fix is proposed in rust-lang/cc-rs#867. However, even if it's resolved, as it turns out, there will be more errors from armasm64. Yes, it means that build/win64/*-armv8.asm weren't actually tested as they are. Naturally because we never had access to a Windows on ARM system. Either way, src/asm/arm-xlate.pl needs more work, but meanwhile could you take #191 for a spin on your system? You would need to add clang to your VS installation, VS Installer provides the option, and make the clang command available on your %PATH% one way or another. By explicitly modifying your %PATH% or invoking cargo in the "Developer Command Prompt for VS." Yeah, inconvenient, but please bear with me...

[dot-asm]

The rust-lang/cc-rs#867 was merged, but it turned out that further adjustments are required, rust-lang/cc-rs#869. But I've fixed up arm-xlate.pl to make assembly work with ARM assembler, so that clang is no longer required. To use blst till updated blst and cc-rs crates are published create .cargo/config.toml in your project or home directory:

[patch.crates-io]
blst = { git = "https://github.com/supranational/blst" }
cc = { git = "https://github.com/rust-lang/cc-rs" }

[dot-asm]

This is resolved to the extent of Windows on ARM build being exercised on Github Actions.

[dot-asm]

Oh! And thanks for the report!