System.Runtime.Intrinsics.Arm.AdvSimd build failure in preview 8

[aik-jahoda]

there is System.Runtime.Intrinsics.Arm.AdvSimd failure in release/5.0-preview8
The problem is visible here:
https://github.com/dotnet/runtime/pull/39434/checks?check_run_id=877743259

error:

TypesMustExist : Type 'System.Runtime.Intrinsics.Arm.AdvSimd' does not exist in the reference but it does exist in the implementation. 

TypesMustExist : Type 'System.Runtime.Intrinsics.Arm.ArmBase' does not exist in the reference but it does exist in the implementation.

It can be caused by #39416

cc @Anipik @jeffhandley

[Dotnet-GitSync-Bot]

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

[ericstj]

This is a duplicate of #39444