gator-daemon: Fix compilation error: 'sa_family_t' does not name a type

gator-daemon: Fix compilation error: 'sa_family_t' does not name a type

When compiling on Linaro Android we get the following error:

bionic/libc/kernel/common/linux/netlink.h:52:2: error: 'sa_family_t' does not name a type
  sa_family_t nl_family;

This is related to an issue that was fixed in Linux 3.1 by commit
6602a4baf4d1a73c (net: Make userland include of netlink.h more sane)
but it seems that the Linux headers used by bionic predate that.

Fortunately, the fix for us is simple: reorder the header file includes
so that the definition of sa_family_t from sys/socket.h is picked up
before being used by linux/netlink.h

Signed-off-by: Jon Medhurst <tixy@linaro.org>