Packaging removal: also revert introduction of sysconfig.cfg.

We need a discussion to define what should be customized how; this new
config file is premature.  It was added to serve the needs of the
resources system in install_data / packaging.database, so it can be
removed alongside packaging for 3.3.
diff --git a/Makefile.pre.in b/Makefile.pre.in
index 682ed32..2156847 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -1031,7 +1031,7 @@
 		else	true; \
 		fi; \
 	done
-	@for i in $(srcdir)/Lib/*.py $(srcdir)/Lib/*.cfg ; \
+	@for i in $(srcdir)/Lib/*.py ; \
 	do \
 		if test -x $$i; then \
 			$(INSTALL_SCRIPT) $$i $(DESTDIR)$(LIBDEST); \