Fix bug in conv rewriter if intermediate node outputs are used (#1498)

Signed-off-by: Tom Wildenhain <[email protected]>

Author: TomWildenhain-Microsoft

tf2onnx/rewriter/conv2d_with_add_rewriter.py

@@ -32,6 +32,8 @@ def rewrite_biasadd_with_conv2d(g, ops):
         conv_output = biasadd.output
         conv_inputs = [conv_input[0], conv_input[1], biasadd.input[1]]
 
+        if len(g.find_output_consumers(conv.output[0])) > 1:
+            continue
         # Remove the Conv and BiasAdd node
         g.remove_node(conv.name)
         g.remove_node(biasadd.name)