Add Otsu's method to cv::cuda::threshold #3943
I implemented Otsu's method in CUDA for a separate project and want to add it to cv::cuda::threshold
I have made an effort to use existing OpenCV functions in my code, but I had some trouble with `ThresholdTypes` and `cv::cuda::calcHist`. I couldn't figure out how to include `precomp.hpp` to get the definition of `ThresholdTypes`. For `cv::cuda::calcHist` I tried adding `opencv_cudaimgproc`, but it creates a circular dependency on `cudaarithm`. I have include a simple implementation of `calcHist` so the code runs, but I would like input on how to use `cv::cuda::calcHist` instead.
### Pull Request Readiness Checklist
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- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [ ] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
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Patch to opencv_extra has the same branch name.
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