dnn: add openvino, opencl and cuda backends for layer normalization layer

[fengyuentau]

Merge after #24544.

Todo:

• openvino
• opencl
• cuda

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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 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.
• The feature is well documented and sample code can be built with the project CMake

force_builders=Linux OpenCL,Win64 OpenCL

[dkurt]

Oh, wait a minute, why we need continue development of LayerNorm layer while there is a new InstanceNorm layer #24378? I expected that LayerNorm should be removed completely.

[fengyuentau]

We agreed previously in the meeting that we keep two classes, and they share similar kernels for CPU.

[dkurt]

Let's see the final state. As far as I remember the only difference between them is scalar or vector scale/bias values,

[fengyuentau]

Let's see the final state. As far as I remember the only difference between them is scalar or vector scale/bias values,

Indexing is also different as well. For Instance Normalization, its indexing is like scale[outer_idx % C]; while for Layer Normalization, its indexing is like scale[j] for j in inner_size.