Rebuild linux toolchains with an older OS. (cherry picked from commit 1d249ad7b592573dc4478f0f6cefe2766c323e12)
Allow toolchain builder to add a suffix to toolchain name. It is useful for rebuilding the same toolchain in different environment. (cherry picked from commit 83148fc5bb4e8bcc5afcf119df53ec1bc854be17)