Revert "dracut: use /run/install/source for repodir"
    
    /mnt/install/source is used by anaconda to mount install media,
    if it finds the boot iso mounted there it will try to unmount it,
    which will fail since we are running from it. Leave it at install/repo
    so that this doesn't happen.
    
    This reverts commit 37144b9e86e801074fa4ae4656da458fe83f6e07.