GpuMat::dataend() is incorrectly calculated in GpuMat::create() meaning that locateROI(wholeSize,ofs) currently returns the stride in wholeSize instead of the width of the ROI when the GpuMat constructor has to allocate device memory internally.

The test case opencv/opencv_contrib#3168 requres a modification to createMat() to return wholeSize and ofs.

This PR will cause cudafilters test cases to fail until opencv/opencv_contrib#3167 is merged.

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

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