Add sysupgrade '-o' option in order to include all overlay files in
backup, except for those that are from packages but including files
listed in conffiles, sysupgrade.conf or /lib/upgrade/keep.d.
With '-u' option, it will skip files equals to /rom and conffiles that
were not changed.
Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
96392e5da4