Add support for Apple visionOS to Conan 1.x

[stevn]

Changelog: (Feature | Fix | Bugfix): Add support for Apple visionOS and apple-clang 15 (currently still beta).
Docs: https://github.com/conan-io/docs/pull/XXXX

Issue link:

#14496

• Refer to the issue that supports this Pull Request.
• If the issue has missing info, explain the purpose/use case/pain/need that covers this Pull Request.
• I've read the Contributing guide.
• I've followed the PEP8 style guides for Python code.
• I've opened another PR in the Conan docs repo to the develop branch, documenting this one.

NOTICE:

• In some cases I am unsure whether to use "xros" or "visionos". I just tried CMake, I don't have resources to test other build systems. I tried to adjust the config scripts for the other build tools accordingly...
• I didn't write any tests.
• It works for me in visionOS 1 beta 2 simulator runtime.

The profile I used:

[settings]
os=visionOS
os.version=1.0
os.sdk=xrsimulator
os.sdk_version=1.0
os_build=Macos
arch=x86_64
arch_build=x86_64
compiler=apple-clang
compiler.version=15
compiler.libcxx=libc++
build_type=Release
[options]
[build_requires]
[env]

[CLAassistant]

All committers have signed the CLA.

[stevn]

The GNU triplet might need to be visionos, not xros...

[memsharded]

Thanks for your contribution @stevn

Conan 1.X is no longer getting this kind of new features. Could you please target it to release/2.0 branch? Thanks!

[stevn]

@memsharded OK. I've added a new pull request for release/2.0: #14504

[stevn]

Closing this since it will only be available in Conan 2.x.