[BUG] HDR10 ot SDR (DG) not work when the "White" is more than 3000!

[Persian]

Seems to be a restriction:

Python exception: DGHDRtoSDR: for PQ white must be 1-3000

Usually the white point is around the max nit of the display, so 3000 seems like a sensicle border for pq.
-> I'll adjust Hybrid to restrict the spinbox to 3000 when pq is selected.
(The limits just weren't properly initiated, when switching mode to 'hlg' and back to 'pq' White is limited to 3000.)

Cu Selur

Thank you very much for your response.