Clean up jitstd folder. (dotnet/coreclr#27542)

Clean up  jitstd folder. (dotnet/coreclr#27542)

* Delete solution files.

They were referencing unexisting files.

* Delete unused files with templates from jitstd.

Many of them have build errors when you instantiate them.

* fix ubuntu build breaks.

The header files did not include the necessary dependencies.

In the past it was ok because the compilation unit included jitstd.h that had #include "utility.h", #include "pair.h", and #include "type_traits.h" before #include "list.h".

Commit migrated from https://github.com/dotnet/coreclr/commit/14b650f35ebeed83e666039a1d3cb2eb7801c666