tools: batch-rebase: Avoid -- with git rev-list
tools: batch-rebase: Avoid -- with git rev-list

git rev-list expects references before -- rather than after for some
reason, even if references are not to be considered as options.

credp/lisa,credp/lisa,ARM-software/lisa,ARM-software/lisa,ARM-software/lisa,credp/lisa,ARM-software/lisa,credp/lisa