revset: remove comment about linkrev workaround from user-facing docs

I think the code is clear enough so we don't need to keep the comment
at all (by now, most Mercurial developers are probably familiar with
the linkrevs issues).

Differential Revision: https://phab.mercurial-scm.org/D6176

mercurial/revset.py

@@ -960,9 +960,6 b' def filelog(repo, subset, x):'
     The pattern without explicit kind like ``glob:`` is expected to be
     relative to the current directory and match against a file exactly
     for efficiency.
-
-    If some linkrev points to revisions filtered by the current repoview, we'll
-    work around it to return a non-filtered value.
     """
 
     # i18n: "filelog" is a keyword