fix(cuda): fix fp16 tensorcore gemm split k workspace

GitOrigin-RevId: d04a0e098541e7e1b519bb392966f598cde3639a

dnn/src/cuda/matrix_mul/cutlass_float16_tensorop_split_k.cpp

@@ -55,12 +55,12 @@ size_t MatrixMulForwardImpl::AlgoFloat16TensorOpSplitK::get_workspace_in_bytes(
         k = args.layout_a.shape[param.transposeA ? 0 : 1];
     int split_k_slices = std::max(1, k / n);
     if (!aligned.first)
-        return args.layout_c.dtype.size(m * n * split_k_slices);
+        return sizeof(float) * (m * n * split_k_slices);
     const auto& layouts = aligned.second;
     int align_m = layouts[2].shape[0], align_n = layouts[2].shape[1],
         align_k = layouts[0].shape[1];
     split_k_slices = std::max(1, align_k / align_n);
-    size_t ws_size = args.layout_c.dtype.size(align_m * align_n * split_k_slices);
+    size_t ws_size = sizeof(float) * (align_m * align_n * split_k_slices);
     for (auto&& ly : layouts)
         ws_size += ly.span().dist_byte();
     return ws_size;