build: make configure.py compatible with python 3

This patch replaces the following

1. Usage of `filter` with `None` to remove falsy items.
2. Usage of `map` to create lists. (Replaced with List comprehensions).
3. Dictionary's `iteritems` which is removed in Python 3.

PR-URL: https://github.com/nodejs/node/pull/25580


Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>