Fix mistake on mat trans 2d when init grid. (#275)

Author: bear-zd

kernels/mat-transpose/mat_transpose.cu

@@ -310,7 +310,7 @@ __global__ void mat_transpose_f32x4_shared_bcf_row2col2d_kernel(
     const int N = x.size(1);                                                                    \
     dim3 block(WARP_SIZE_S, WARP_SIZE_S);                                                       \
     dim3 grid((N + WARP_SIZE_S - 1) / (WARP_SIZE_S * n_element_col),                            \
-              (M + WARP_SIZE_S - 1) / (WARP_SIZE_S / n_element_row));                           \
+              (M + WARP_SIZE_S - 1) / (WARP_SIZE_S * n_element_row));                           \
     mat_transpose_##tag##2d_kernel <<<grid, block>>>(                                           \
       reinterpret_cast<element_type *>(x.data_ptr()),                                           \
       reinterpret_cast<element_type *>(y.data_ptr()), M, N);                                    \