resolve: support commands.resolve.confirm option with --mark flag
Now, commands.resolve.confirm config option also respect --mark; and
confirm to mark all 'unresolved' files as 'resolved'.
It will confirm only when you don't pass any pats i.e 'hg resolve -m',
because when no file pats are passed then --mark's default functionality
is to mark all unresolved files.
And if user has given file pats then I think there is no need to confirm.
Differential Revision: https://phab.mercurial-scm.org/D4101