fix policy Makefile for RHEL4/5

commit 7c31f1c7a64635b5216996dd0e4de014af762a79 breaks build for RHEL4/5:
  make[2]: Leaving directory
  `/root/selinux-testsuite/policy/redhat/5/test_policy'
  make[1]: *** No rule to make target `exit'.  Stop.
  make[1]: Leaving directory `/root/selinux-testsuite/policy/redhat/5'

There are 2 problems:
  1. missing semi-colon before exit
  2. exit won't stop target execution, so it continues and tries to build
     general policy

This patch removes duplicate tests for RHEL version and defines
rhel/general variant of build/load/unload. The only remaining ifeq test
then decides which variant will be used.

Tested on RHEL5.3, RHEL6.0, RHEL6.4, RHEL-7.0-20131018.0(pre-beta)

Signed-off-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
capable_net: check for ifconfig in different locations

Pardon my C-like Perl, but in current Fedora Rawhide releases we need
to check for ifconfig in /usr/bin and not just /sbin.

Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Serge Hallyn <serge@taiga.selinuxproject.org>