kconfigini: block loading of too large files

Harald Sitterrequested to merge
work/sitter/etoolarge into master

I know of at least two cases where large files broke things

one is CCBUG: 510966

the other was some defect in plasma where we leaked infinite amounts of data into the config and eventually ended up blocking the gui while parsing it.

refuse to load large files instead, in lieu of an actual use case. plus performance will likely be horrible anyway with the current code

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