[FS#1512] uhttpd: no install of certs for https

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Reiner Otto (reinerotto) 

Attached to Project - OpenWrt/LEDE Project
Summary - uhttpd: no install of certs for https
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Medium
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - Installation of uhttpd-package without openssl should use px5g to generate certs, to be used for https.
This was the state some time in the past, at least.
Now, px5g is not automatically installed, in case no openssl built, and even manual inclusion of px5g to be included in image is not sufficient, because of a reference to /lib/libustream-ssl.so in /etc/init.d/uhttpd. 

Reproduce: Build a custom image, incl. uhttpd, but without any openssl.
After boot, uhttpd will listen on port 80 only.

More information can be found at the following URL:
https://bugs.openwrt.org/index.php?do=details&task_id=1512