destutil: remove redundant examination

Before this patch, "len(heads) != len(otherheads)" is examined to
detect whether message should be displayed or not.

But if "repo.revs('%ln and parents()', heads)", heads should contain
"parents()" and otherheads is always less than heads.

mercurial/destutil.py

@@ -357,11 +357,10 b' def _statusotherbook(ui, repo):'
 def _statusotherbranchheads(ui, repo):
     currentbranch = repo.dirstate.branch()
     heads = repo.branchheads(currentbranch)
-    l = len(heads)
     if repo.revs('%ln and parents()', heads):
         # we are on a head
         otherheads = repo.revs('%ln - parents()', heads)
-        if otherheads and l != len(otherheads):
+        if otherheads:
             ui.status(_('%i other heads for branch "%s"\n') %
                       (len(otherheads), currentbranch))