Med: Don't preserve SELinux context when copying files to /var/lib/nfs/sm

Pass the flags -Rdpf instead of -af to cp when copying files to
/var/lib/nfs/sm so that the SELinux context is inherited from the
target directory and not preserved from the files being copied.

Resolves: rhbz#907898

Signed-off-by: Ryan McCabe <rmccabe@redhat.com>