rgbd: fix segmentation fault on Arm 32bit platform

[tomoaki0705]

resolves #2857

Pull Request Readiness Checklist

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• 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 other license that is incompatible with OpenCV
• The PR is proposed to proper branch
• There is reference to 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.
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force_builders=Custom
build_image:Custom=ubuntu32:16.04
buildworker:Custom=linux-1,linux-4,linux-6

[tomoaki0705]

I think I need a help for build failure on armv7
The message seems to be irrelevant from my fix

/build/precommit-contrib_armv7/opencv/modules/core/include/opencv2/core/cuda.hpp:456:15: error: function 'cv::cuda::GpuMatND& cv::cuda::GpuMatND::operator=(cv::cuda::GpuMatND&&)' defaulted on its first declaration with an exception-specification that differs from the implicit declaration 'cv::cuda::GpuMatND& cv::cuda::GpuMatND::operator=(cv::cuda::GpuMatND&&)'
     GpuMatND& operator=(GpuMatND&&) noexcept = default;

Yet, other machines are building fine, when just armv7 is failing.
I've gone wrong in my recent PRs, claiming "It's not my fault" when it was.
Can anyone advice me if it's my failure or is this known issue ?

[alalek]

Right, you can ignore that.
Relates: opencv/opencv#19259
I will prepare a hotfix tomorrow. Done: opencv/opencv#19466

[savuor]

The true mistake here is that a result of register comparison is float register, while it expected (by the author) to be integer register. So the result could be simply reinterpreted as (u)int32.
But this code is also correct, so 👍