[master] Update dependencies from dotnet/corefx (#23893)
* Update dependencies from https://github.com/dotnet/corefx build
20190411.2
- Microsoft.NETCore.Platforms - 3.0.0-preview5.19211.2
- Microsoft.Private.CoreFx.NETCoreApp - 4.6.0-preview5.19211.2
* Update dependencies from https://github.com/dotnet/corefx build
20190411.22
- Microsoft.NETCore.Platforms - 3.0.0-preview5.19211.22
- Microsoft.Private.CoreFx.NETCoreApp - 4.6.0-preview5.19211.22
* Removing renamed HWIntrinsic APIs from S.P.Corelib
* Updating the hwintrinsiclistxarch to match the new intrinsic API names
* Updating the HWIntrinsic generated tests to use the new API names