So far, we define PORTORDER individually in each network.* file.
This creates a lot of duplications, and makes the code to parse those
values very ugly (and it's only used outside of configurenetwork
anyway).
Therefore, move the assignment to a library file, and wrap it into
a function for tidyness. This gives us more overview and nicer
implementation of the retrieval.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Acked-by: Christian Dresel <freifunk@dresel.systems>
Reviewed-by: Robert Langhammer <rlanghammer@web.de>