[vlpp] Fix configure issues, export unofficial target

[JackBoosY]

This PR is trying to fix the configure issues in vcpkg.

Related: https://github.com/vczh-libraries/Release/pull/13

[JackBoosY]

cc @vczh

[JackBoosY]

I saw https://github.com/vczh-libraries/Release/tree/master/Import has many source files, but I don't know what files should be corresponding to the features. I looked up the documentation but couldn't find instructions.

[JackBoosY]

Is there a public record of the actual problems?

Trying to have communication in Teams internal.

[JackBoosY]

arm64-windows:

D:\buildtrees\vlpp\src\89147234d4-66da526de7.clean\Import\VlppOS.Windows.cpp(1782): error C3861: '_mm_pause': identifier not found

x64-osx:

/Users/vagrant/Data/buildtrees/vlpp/src/89147234d4-66da526de7.clean/Import/VlppOS.Linux.cpp:51:17: error: use of undeclared identifier 'PATH_MAX'
                                char buffer[PATH_MAX] = { 0 };
                                            ^
/Users/vagrant/Data/buildtrees/vlpp/src/89147234d4-66da526de7.clean/Import/VlppOS.Linux.cpp:52:20: error: use of undeclared identifier 'PATH_MAX'

x64-linux:

/mnt/vcpkg-ci/buildtrees/vlpp/src/89147234d4-66da526de7.clean/Import/VlppOS.Linux.cpp:1539:20: error: ‘_mm_pause’ was not declared in this scope
 1539 |    while(token!=0) _mm_pause();
      |                    ^~~~~~~~~

[JackBoosY]

@vczh any ideas with the regressions?

[JackBoosY]

Waiting for internal discuss result.

[JackBoosY]

Will request review again after header path issues are fixed by merge the upstream PR https://github.com/vczh-libraries/GacUI/pull/85 and https://github.com/vczh-libraries/Workflow/pull/4.