Build fix

/build/build_cuda/3p/opencv/linux-x64/ubuntu22.04/Debug/modules/dnn/src/layers/cpu_kernels/convolution.cpp: In function 'void cv::dnn::packData8(char*&, float*&, int&, int&, int&, const int*, int, int, int)':
/build/build_cuda/3p/opencv/linux-x64/ubuntu22.04/Debug/modules/dnn/src/layers/cpu_kernels/convolution.cpp:448:43: error: 'CONV_NR' was not declared in this scope; did you mean 'CONV_3D'?
  448 |                 vx_store(inpbufC_FP32 + k*CONV_NR, vx_load(inptrInC + k1));
      |                                           ^~~~~~~
      |                                           CONV_3D

modules/dnn/src/layers/cpu_kernels/convolution.cpp

@@ -445,7 +445,7 @@ static inline void packData8(char*& inpbuf, float*& inptrIn, int& in_w, int& x0,
             {
                 int k1 = ofstab[k];
 #if CV_SIMD256
-                vx_store(inpbufC_FP32 + k*CONV_NR, vx_load(inptrInC + k1));
+                vx_store(inpbufC_FP32 + k*CONV_NR_FP32, vx_load(inptrInC + k1));
 #elif CV_SIMD128
                 v_float32x4 vv0 = v_load(inptrInC + k1);
                 v_float32x4 vv1 = v_load(inptrInC + k1 + 4);