Issue #12131: Ensure that the sysconfig.cfg file, introduced by packaging,
is installed into the lib directory: prevents startup exception in site.py.
diff --git a/Makefile.pre.in b/Makefile.pre.in
index e8624ed..04d126f 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -947,7 +947,7 @@
 		else	true; \
 		fi; \
 	done
-	@for i in $(srcdir)/Lib/*.py $(srcdir)/Lib/*.egg-info ; \
+	@for i in $(srcdir)/Lib/*.py $(srcdir)/Lib/*.egg-info $(srcdir)/Lib/*.cfg ; \
 	do \
 		if test -x $$i; then \
 			$(INSTALL_SCRIPT) $$i $(DESTDIR)$(LIBDEST); \