Do not check if SELinux is enabled on lowlevel calls to set processlabel

docker exec changes the mount namespace which fools selinux bindings
into thinking SELinux is disabled.  Bindings should just check if
a label is passed in and attempt to use it.  Docker will not call these
functions with a label if SELinux is disabled.

Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
Merge pull request #222 from rhatdan/exec

Do not check if SELinux is enabled on lowlevel calls to set processlabel
Set apparmor profile in execin

The set of the apparmor profile for the setns codepath was missing.
Selinux was being called but apparmor was forgotten.  This was causing
no profiles to be applied to the extra process spawn inside an existing
container.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Merge pull request #224 from crosbymichael/set-apparmor-execin

Set apparmor profile in execin
xattr: Disallow build on non linux platforms

Signed-off-by: Harshavardhana <fharshav@redhat.com>