lib: include the Config file too

The lib makefile doesn't include Config which means it misses
setting up toolchain vars that it includes.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

lib/Makefile

+include ../Config
+
 CFLAGS += -fPIC
 
 UTILOBJ=utils.o rt_names.o ll_types.o ll_proto.o ll_addr.o inet_proto.o