simplify old linux remote fix

Hi, your docs at https://code.visualstudio.com/docs/remote/faq#_can-i-run-vs-code-server-on-older-linux-distributions are confusing at best.

I took a few moments to read between the tea leaves. And came up with this:

https://gist.github.com/dotysan/1c4c1dff8f9a62ec7fb14950c456dfae

It attempts to build a vscode-compatible sysroot on the old linux remote server in one step.
