Move macOS remote unwinding to libunwind directory

[am11]

We were duplicating headers between Windows and macOS remote unwind code. This PR applies upstream patch from libunwind/libunwind#365 and adjusts our local cmake configs to deduplicate the code.

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Issue Details

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We were duplicating headers between Windows and macOS remote unwind code. This PR applies upstream patch from libunwind/libunwind#365 and adjusts our local cmake configs to deduplicate the code.

Author:	am11
Assignees:	-
Labels:	area-Infrastructure-libraries, community-contribution
Milestone:	-

[am11]

cc @janvorli, @AaronRobinsonMSFT, @jkotas
The missing functions on Windows for remote unwind were added to libunwind in libunwind/libunwind@693f30a, this PR moves macOS missing functions on the same plan and aligns file naming.

[am11]

wasm failure is unrelated. (#69806?)
@janvorli, PTAL.

[AaronRobinsonMSFT]

@am11 I think we are just waiting to see if the upstream changes get taken. I like the clean-up for sure. Any concerns about upstream acceptance?

[am11]

@AaronRobinsonMSFT, in the past, we have upstreamed in parallel like this. It is totally reasonable to hold this PR until upstream one is reviewed/merged. There is no rush.

I am planning on upstreaming two remaining items after this:

1. JanV's 1b5719c
2. Revive Add _OOP_find_proc_info libunwind/libunwind#187 by molding it into pattern used by Expose function-pointer-to-name API libunwind/libunwind#299 (manpage, basic test and build options). That will cleanup src/native/external/libunwind_extras/oop from our side (among few adjustments for "use system libunwind" case; run-time / version-based check to consume this new API).

[AaronRobinsonMSFT]

It is totally reasonable to hold this PR until upstream one is reviewed/merged

Glad we are on the same page. That is really the only reason I haven't merged this in.

[janvorli]

LGTM, thank you! I am sorry for the big delay, my github account somehow decided that my email is no longer valid and stopped sending me notifications on comments / PR requests and I've missed this one.

[AaronRobinsonMSFT]

@am11 Seems like the libunwind changes were merged into main. Let's make sure this is still green and then get it in.

[am11]

The changes made in upstream directory src/native/external/libunwind in main has no upstream PR/commit at all, has no mention in libunwind-version.txt entry and they are unnecessary changes (do not contribute in build in runtime repo at all). We should revert them to keep things synchronized..

[am11]

@AaronRobinsonMSFT, upstream PR is merged now.