Building singlefilehost with clr partition.

[VSadov]

• single file host builds with clr partition
• removed hacks that align single file host build flavor and CRT to match with clr
• host build script now just picks singlefilehost executable from clr artifacts
• fixed a few places which introduce duplicate definitions when JIT and VM are linked together.

NOTE: static libs for the native libraries that are built in clr partitions are still installed into artifacts.
I left them be, in case there are other uses, but singlefilehost no longer needs them.

Resolves:#43700

[ghost]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[VSadov]

I think this is ready for review.

[VSadov]

This change was needed to not include resources in the statically linked JIT.

[VSadov]

these /wd defined for everything in host.native .
Since we build this separately from others now, I had to add the options here.

[VSadov]

I am very happy that this is gone. It seemed very fragile.

[janvorli]

LGTM, thank you!

[VSadov]

Thanks!!!

[ghost]

Hello @VSadov!

Because this pull request has the auto-merge label, I will be glad to assist with helping to merge this pull request once all check-in policies pass.

p.s. you can customize the way I help with merging this pull request, such as holding this pull request until a specific person approves. Simply @mention me (@msftbot) and give me an instruction to get started! Learn more here.

[BruceForstall]

@VSadov It appears this change broke the JIT rolling build (which only builds the JIT, using, for example, src/coreclr/build-runtime.cmd checked x64 -ci -skipruntime -nopgooptimize -skiprestoreoptdata):

https://dev.azure.com/dnceng/internal/_build/results?buildId=1004132&view=results

cc @dotnet/jit-contrib

[am11]

@BruceForstall, I have opened #48552 with the fix. The condition just need to include corehost directory conditionally.