refpolicy: run setfiles only if $D is not set

Running this setfiles command only applies for the target. Check for existence of $D,
which is only defined for the build environment. If $D is not defined, we're running
on the target, so execute setfiles.
Merge pull request #29 from bennettj1087/selinux-setfiles-fix-2

[v2] refpolicy: run setfiles only if $D is not set
[OXT-74] Delete insane class.

This is a duplicate of the class in the openembedded-core repo. The
only change we've made is reducing LIC_FILES_CHKSUM errors from ERROR
to WARNING.
[OXT-74] Fix license hash for kmod.
[OXT-74] Fix license check in rt3572.

Not sure what the comment in this file was all about. The method
employed here works AFAIK.
[OXT-74] Fix license hash in pciutils.
[OXT-74] Remove dependency on task-xenclient-dom0-extra from xenclient-dom0-image.

This task has no license data and is an NO-OP anyways.
[OXT-74] Add bbappend for ipsec-tools to fix license hash.

Weird that the upstream meta-openembedded layer has a bad hash ...