revset: drop some unused code in the `remote` revset

PyCharm flagged the `revs = [..]` as an unused assignment.  But then neither
`revs` nor `checkout` is used, and I can't see where `hg.addbranchrevs()` has
external side effects.

Differential Revision: https://phab.mercurial-scm.org/D7764

mercurial/revset.py

@@ -2025,9 +2025,7 b' def remote(repo, subset, x):'
         dest = getstring(l[1], _(b"remote requires a repository path"))
     dest = repo.ui.expandpath(dest or b'default')
     dest, branches = hg.parseurl(dest)
-    revs, checkout = hg.addbranchrevs(repo, repo, branches, [])
-    if revs:
-        revs = [repo.lookup(rev) for rev in revs]
+
     other = hg.peer(repo, {}, dest)
     n = other.lookup(q)
     if n in repo: