LineageOS recently took over the now-deceased CyanogenMod custom ROM platform which specialized in providing a customizable way to enjoy various smartphones. So far, we’ve seen various builds for the Nexus 6P/5X, Moto G4, OnePlus 2, and more pop up on the internet, but none of them come with root. That said, the developers behind the ROM have today released the official ZIP file which allows users to root any build of LineageOS. In order to go about doing so, just download the file to your device, boot into your custom recovery (I always prefer TWRP), flash the ZIP, and reboot. You’ll then be fully rooted and ready to enjoy all the pleasures and perks surrounding the custom software.
Interestingly, this method of rooting uses Superuser and not SuperSU, but you can obviously still find a flashable SuperSU ZIP and use this instead. However, it’s worth noting that the Superuser method (the one listed here) is the only recommended way of rooting LineageOS. But since you’re still gutsy enough to hack your device like you’ve already done, I guess it doesn’t make a difference which method you use.
You can download the official ZIP file here.