iproute2: use -fPIC in lib/

The static libnetlink.a library is exposed to other users in Debian via the
"iproute-dev" package. Apparently people are interested in using it in their
shared libraries and would like to see the code be position independent.

Patch below makes the code under lib/ build with -fPIC.

See http://bugs.debian.org/547602Signed-off-by: Andreas Henriksson <andreas@fatal.se>

lib/Makefile

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