fix map link in custom banner

[maurerle]

Before, this produced URLs like https://map.ffmuc.net/#!{NODEID} which do not work

[T0biii]

z.B. https://map.ffmuc.net/#!/4682d327ec74 works for me fine

[grische]

@maurerle works on my machine

[grische]

We do not want to bias the default language of the link.
Works for both ffmuc and ffac. Examples:

• https://map.aachen.freifunk.net/#!/d41ad113b63c
• https://map.ffmuc.net/#!/4682d327ec74

[T0biii]

ah i see in your Site file: ffac/site@cc608e0
there was a missing / at the end

[maurerle]

Thanks! :)