Merge pull request #23853 from fengyuentau:disable_fp16_warning

dnn: disable warning when loading a fp16 model #23853

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- [x] I agree to contribute to the project under Apache 2 License.
- [x] 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
- [x] 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

modules/dnn/src/onnx/onnx_graph_simplifier.cpp

@@ -1125,7 +1125,7 @@ Mat getMatFromTensor(const opencv_onnx::TensorProto& tensor_proto)
     else if (datatype == opencv_onnx::TensorProto_DataType_FLOAT16)
     {
         // FIXME, for now, we only load FP16 Tensor as FP32 Mat, full support for FP16 is required in the future.
-        CV_LOG_ONCE_WARNING(NULL, "DNN: load FP16 model as FP32 model, and it takes twice the FP16 RAM requirement.");
+        CV_LOG_ONCE_INFO(NULL, "DNN: load FP16 model as FP32 model, and it takes twice the FP16 RAM requirement.");
 
         // ONNX saves float 16 data in two format: int32 and raw_data.
         // Link: https://github.com/onnx/onnx/issues/4460#issuecomment-1224373746