[3dprinter-general] Missing symbols in libArcus for arch:armel

[Gregor Riepl]

>> I hope this will retrigger a build of CuraEngine on arch:armel. I has failed
>> already due to the missing dependency...
> 
> It will.

Very good.

> I did a test build on abel.debian.org, and the build in git still fail
> for armel. :(

Thanks!
Looks like I missed another symbol...
I really, really need to start using pkgkde-symbolhelper.

Please test again with the latest commit, when you can.