[Transformation] Add condition that reshape node is inbetween two fpgadataflow nodes to trafo

src/finn/transformation/move_reshape.py

 from finn.transformation import Transformation
-from finn.transformation.infer_shapes import InferShapes
+from finn.util.basic import get_by_name
 
 
-def _get_number_of_nodes(model):
-    node_count = 0
-    for n in model.graph.node:
-        node_count += 1
-    return node_count
+def _is_fpgadataflow_node(node):
+    if node is not None:
+        if node.domain == "finn":
+            n_backend = get_by_name(node.attribute, "backend")
+            if n_backend is None:
+                return False
+            backend_value = n_backend.s.decode("UTF-8")
+            if backend_value == "fpgadataflow":
+                return True
+        else:
+            return False
+    else:
+        return False
 
 
 class MoveReshape(Transformation):
-    """Removes a node that implements a (1, -1) reshape and runs
-    InferShapes on the model"""
+    """Removes a node that implements a (1, -1) reshape if it is
+    between two fpgadataflow nodes"""
 
     def apply(self, model):
 
@@ -22,10 +30,11 @@ class MoveReshape(Transformation):
                 graph_modified = True
                 shape = model.get_initializer(n.input[1])
                 if (shape == [1, -1]).all():
-                    consumer = model.find_consumer(n.output[0])
-                    if consumer is not None:
-                        consumer.input[0] = n.input[0]
-                    graph.node.remove(n)
+                    producer = model.find_producer(n.input[0])
+                    if _is_fpgadataflow_node(producer) is True:
+                        consumer = model.find_consumer(n.output[0])
+                        if _is_fpgadataflow_node(consumer) is True:
+                            consumer.input[0] = n.input[0]
+                            graph.node.remove(n)
 
-        model = model.transform(InferShapes())
         return (model, graph_modified)