Makefile.am referenced a now non-existing config-win32.h

This file was moved to win/config.h.in and is the template used
by the Python build tools in win/.  This happened in
commit 4b312378e9e7084a0699ca6d4b895bdadb7540db

For all other autotools based environments, ./configure will take
care of creating the proper config.h

Signed-off-by: David Sommerseth <davids@redhat.com>
Acked-by: Gert Doering <gert@greenie.muc.de>

Author: David Sommerseth