Make native mvnd only require glibc 2.12 on ubuntu 22.04 (#825, fixes #823)

The modern glibc from 2.34 had two breaking changes: move all api in lib{pthread,dl,rt}.so into libc.so, new static start up code breaking the runtime compatibility for old glibc (<2.34). See https://developers.redhat.com/articles/2021/12/17/why-glibc-234-removed-libpthread for more info.

This commit has 3 changes to overcome these changes:
- override gcc path to redefine glibc symbols on the fly in the generated .o by graalvm when linking
- provide a dynamic startup code to support both old and modern runtime glibc
- add needed dynamic libraries: lib{pthread,rt,dl}.so.
8 files changed