Bug 1734879 - Accept arch and os version as init params on Qt

[brizental]

I know we discussed making these values enums maybe, but for os version that is just not possible and for architecture that would be hard, see https://doc.qt.io/qt-5/qsysinfo.html#currentCpuArchitecture, we don't have a list of all the possible values returned by the Qt function that retrieves that value.

I think this is fine though, because different from what we thought yesterday, GLAM does not use the architecture field for creating filters, it uses only OS and channel.

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