openssh: selinux and pam support

[Thomas: in the sed expression, use % as a delimiter instead of /,
since the line contains several / that all had to be escaped.]

Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
Reviewed-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>