Hi.
Please consider adding tvheadend-git package, I compiled the non Arm package with no issue on my Pogoplug 4.
https://aur.archlinux.org/packages/tvheadend-git/
There's a package for the official stable tvheadend releases, you may want also to add it.
https://aur.archlinux.org/packages/tvheadend/
I prefer the more updated git version as lately tvheadend updating constantly and fast with more features added and becoming more stable.
Thanks.