clean up list of disabled warnings. (dotnet/coreclr#18318)

clean up list of disabled warnings. (dotnet/coreclr#18318)

* delete warnings that do not longer exist

For example C4171 was deleted after VS 6.0 (https://docs.microsoft.com/en-us/previous-versions/visualstudio/visual-studio-6.0/aa233011(v=vs.60))

* delete C4206 fromm the list

because its default value is 4, so this line is useless.

* reenable warning as error.

* enable warning C4430

and fix places that trigger it.

* fix C4334

* format the list

* fix ssize_t

Commit migrated from https://github.com/dotnet/coreclr/commit/1c8c96ec2bb52368124928648d7557ac85ff9c40