Lenet operators

Added backend_cuda for the following operators:

• AvgPooling
• FC/Gemm
• MaxPooling
• ReLU

include/aidge/backend/cuda/operator/FCImpl.hpp

+/********************************************************************************
+ * Copyright (c) 2023 CEA-List
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ ********************************************************************************/
+
+#ifndef AIDGE_BACKEND_CUDA_OPERATOR_FCIMPL_H_
+#define AIDGE_BACKEND_CUDA_OPERATOR_FCIMPL_H_
+
+#include <array>
+#include <memory>
+#include <tuple>
+#include <vector>
+
+#include <cudnn.h>
+
+#include "aidge/backend/OperatorImpl.hpp"
+#include "aidge/operator/FC.hpp"
+#include "aidge/utils/Registrar.hpp"
+#include "aidge/utils/Types.h"
+
+#include "aidge/backend/cuda/utils/CudaUtils.hpp"
+
+namespace Aidge {
+class FCImplForward_cuda : public Registrable<FCImplForward_cuda,
+                                                 std::tuple<DataType>,
+                                                 void(unsigned int , unsigned int , unsigned int, bool, const void* , const void* , const void* , void*)> {};
+class FCImpl_cuda : public OperatorImpl {
+private:
+    // CuDNN specific variables
+
+
+public:
+    FCImpl_cuda(const FC_Op &op) : OperatorImpl(op) {}
+
+    static std::unique_ptr<FCImpl_cuda> create(const FC_Op &op) {
+        return std::make_unique<FCImpl_cuda>(op);
+    }
+
+public:
+    void forward();
+    // ~FCImpl_cuda();
+
+private:
+    template <class T> void forward_(const Tensor& input0, const Tensor& input1, const Tensor& input2, bool noBias, DimSize_t outChannels);
+};
+
+namespace {
+// add cuda backend to FC_Op implementation registry
+static Registrar<FC_Op> registrarFCImpl_cuda("cuda", Aidge::FCImpl_cuda::create);
+}  // namespace
+}  // namespace Aidge
+
+#endif /* AIDGE_BACKEND_CUDA_OPERATOR_FCIMPL_H_ */