Build for Netgear R7800

Just test it, run the scripts ans see, if the results are as expected.

Ps.
you can see my own ar71xx versions of the scripts from the WNDR3700 community build. Just check the "main".patch of the 17.01 release if you want 17.01.

https://www.dropbox.com/sh/t52c02rm20y8x9p/AADTETYgu1LycB26BFTYOUkGa/lede1701-r3506-bb6a8b2cbf-20170906/WNDR3700-lede1701-r3506-bb6a8b2cbf-20170906-2058-main.patch?dl=0
(line 520 forward)