Prepending --login to the argument list of BackendCmd.sudo() fails if
run as root, because BackendCmd.sudo() detects that and leaves the
/usr/bin/sudo out from the exec call. Fix that by adding an
opts: list[str] parameter to sudo, defaulting to an empty list, with
options that should be passed to /usr/bin/sudo.
Signed-off-by: Jan Lindemann <jan@janware.com>