[FS#189] porassl or opkg or another (r1681) - canot install this pakages too image from booildbot

[LEDE Bugs]

The following task has a new comment added:

FS#189 - porassl or opkg or another (r1681) - canot install this pakages too image from booildbot
User who did this - Matthias Schiffer (NeoRaider)

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Okay, there are two underlying issues:


  * There are no rules preventing different libustream versions to be selected at the same time
  * LuCI has an unconditional dependency on libustream-polarssl

My recent change removing --force-overwrite from the opkg install call caused this issue to pop up. I don't think reverting the change is a good idea, as allowing to install two packages providing the same file isn't sane at all; we should rather fix the actual issues.
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=189#comment487