python: Add fallbacks for packages that have been renamed

Python 3 has restructured some packages. Specifically, __builtin__ has
been renamed to builtins and urlparse has been included in urllib.

Change-Id: I81f8f3942471db1043006a36abbad6e5a49e0a43
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15994
Reviewed-by: Juha Jäykkä <juha.jaykka@arm.com>
2 files changed