logcmdutil: let getlinerangerevs() return "revs" as a smartset...
logcmdutil: let getlinerangerevs() return "revs" as a smartset
This makes it consistent in "hg log" command where 'revs' can come from
logcmdutil.getrevs() as a smartset or from getlinerangerevs(),
previously as a list. This will help type hinting as noticed in
https://phab.mercurial-scm.org/D7377.