stereo: performance optimization of sgm on Window-ARM64

[pratham-mcw]

Pull Request Readiness Checklist

• This PR adds an ARM64 NEON intrinsics-based optimization for the computeDisparityBinarySGBM function in stereo_binary_sgbm.cpp.
• The new implementation uses NEON vector instructions (e.g., vld1q_s16, vminq_s16, vqaddq_s16), allowing for efficient parallel computation. This is guarded under the CV_NEON macro and does not affect other platforms.
• This change is similar to existing SSE2 optimizations for x64 and brings the same performance benefits to ARM64.

Performance Improvements:

• The optimization significantly improves the performance of sgm on Windows ARM64 targets.
• The table below shows timing comparisons before and after the optimization:

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