fix invalid HTTPS check

[grische]

The old code ran wget and checked only if exit code was '1' and then used HTTP as a fallback.

wget returns several different exit code:
https://www.gnu.org/software/wget/manual/html_node/Exit-Status.html

In case for example an "SSL verification failure." occured (expired certs) the fallback did not trigger and it tried but failed to establish an HTTPS connection.

[grische]

This needs some more discussion as this logic change might have unintended side-effects.
Currently, an existing Gluon router does:

root@ffmuc-d88xxxxxxxxxx:~# wget -q https://[[::1]]
Failed to send request: Operation not permitted
root@ffmuc-d88xxxxxxxxxx:~# echo $?
4

[maurerle]

If no ssl lib is installed,
wget -q "https://[::1] returns 1 (do not know what to do - generic) -> use http
if any lib is installed:
wget -q "https://[::1] returns 4 (network error) -> https is available and can be used

So checking for 0 or not equals 0 does not help here.
Maybe there is a better way to check if any ssl lib is installed

[grische]

Yeah, that's also we just figured out in ffmuc. So either checking for -ne 4 or -eq 1. I will close this for now