[arcusbuilds]

cuda::multiply and cuda::sqr computed 16-bit products in int without saturating (65535*65535 gave 0) and wrapped 32S products written as CV_32F; this saturates the 16-bit results and computes 32S to float in double, while CV_32S output still wraps. Fixes #4213
Adds overflow regression tests to test_element_operations.cpp with literal 16-bit expected results.
Built with CUDA on sm_89 and ran the new tests plus the cudaarithm test suite.

Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

• I agree to contribute to the project under Apache 2 License.
• 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
• There is accuracy test, performance test and test data in opencv_extra repository, if applicable
  Patch to opencv_extra has the same branch name.
• The feature is well documented and sample code can be built with the project CMake