Add support for Windows Aarch64

[GulinSS]

See details: https://gitlab.haskell.org/ghc/ghc/-/issues/24603#note_565835

[GulinSS]

Workflow:

ERROR: The running command stopped because the preference variable "ErrorActionPreference" or common parameter is set to Stop: Cannot find path 'C:\WORK\s\appveyor\AppData\Roaming\cabal\config' because it does not exist.

I am not sure how it is related to the change proposed by the PR. 🤔 Could anyone help with it?

[RyanGlScott]

This isn't strictly necessary to make the library compile on ARM, but I wonder if this module should also define bindings to ARM64-specific registers from ARM64_NT_CONTEXT. (As I understand it, this is the ARM64 equivalent of CONTEXT on x86-64.)

[GulinSS]

Can you add details which ARM64-specific registers do you expect should have been added? These ones?

Sp
Pc
Fpcr
Fpsr

[RyanGlScott]

System.Win32.DebugApi defines general-purpose x86-64 registers, so at a minimum, I think we should include the general-purpose ARM64 registers (X0 through X28, Fp, and Lr). Moreover, System.Win32.DebugApi also defines the x86-64 stack pointer (rsp) and instruction pointer (rip), so I think we should also offer the ARM64 counterparts (Sp and Pc) for consistency.

I don't have a strong feeling about the other registers in ARM64_NT_CONTEXT, so I think it would be fine to omit them. (System.Win32.DebugApi doesn't currently offer bindings to all of the registers in the x86-64 CONTEXT struct, so this is consistent with existing precedent.)

[GulinSS]

Done

[Mistuke]

Thanks for the PR. I'm somewhat curious about some of the host arch additions, but I'll take a closer look tomorrow.

Though I do wonder if the checks shouldn't be on target arch instead. I'm aware the current ones are on host arch.

@angerman have you folks run into issues here cross compiling to windows?