contrib/editmergeps.bat

revlog: reorder a conditionnal about revlogio

if we are using REVLOGV0, we will not use a rust based index. This small line
movement make it clearer.

Differential Revision: https://phab.mercurial-scm.org/D7830

@echo off
powershell -NoProfile -ExecutionPolicy unrestricted -Command "& '%~dp0\editmergeps.ps1' %*"