[BUG] git-rev-list: --topo-order --boundary and --max-count

Hi *,

  the --topo-order does not play well with --boundary and --max-count.

$ git-rev-list --boundary --max-count=50 5ced0 | wc -l
56
$ git-rev-list --topo-order --boundary --max-count=50 5ced0 | wc -l
8846

(5ced0 is git.git's master). I think it should be 56 for both. It
presents this behaviour since c4025103fa, when was added --boundary
support for git-rev-list --max-count and --max-age.

Santi