- add a test to check values for /machine argument
- add a test to check if machine is correctly inferred from inputs

This reverts commit 5d529c32cc2d5342a0d183881b6c3023435ed5d3.

- add a test to check values for /machine argument
- add a test to check if machine is correctly inferred from inputs

Similar to D125411, but for ARM64X.

ARM64X PE binaries are hybrids containing both ARM64EC and pure ARM64
variants in one file. They are usually linked by passing separate
ARM64EC and ARM64 object files to linker. Linked binaries use ARM64
machine and contain additional CHPE metadata in their load config.
CHPE metadata support is not part of this patch, I plan to send that later.

Using ARM64X as a machine type of object files themselves is somewhat
ambiguous, but such files are allowed by MSVC. It treats them as ARM64
or ARM64EC object, depending on the context. Such objects can be
produced with cvtres.exe -machine:arm64x.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D148517

This is the first patch of a patchset to add initial support for
ARM64EC. Basic documentation is available at
https://docs.microsoft.com/en-us/windows/uwp/porting/arm64ec-abi .
(Discourse post:
https://discourse.llvm.org/t/initial-patches-for-arm64ec-windows-11-now-posted/62449
.)

The file format for ARM64EC is basically identical to normal ARM64.
There are a few extra sections, but the existing code for reading ARM64
object files just works.

Differential Revision: https://reviews.llvm.org/D125411

r363016 let lld-link and llvm-lib share the /machine: parsing code.
This lets llvm-cvtres share it as well.

Making llvm-cvtres depend on llvm-lib seemed a bit strange (it doesn't
need llvm-lib's dependencies on BinaryFormat and BitReader) and I
couldn't find a good place to put this code. Since it's just a few
lines, put it in lib/Object for now.

Differential Revision: https://reviews.llvm.org/D63120

llvm-svn: 363144