fixed memory freeing if error during listing services

Signed-off-by: Radoslaw Pajak <r.pajak@samsung.com>
Reviewed-by: Simon McVittie <simon.mcvittie@collabora.co.uk>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=71526
NEWS
NEWS for the SELinux change
Merge branch 'dbus-1.6'