Take graph topology into account when creating dnnl subgraphs (#7910)
Check the inputs of all nodes are part of the subgraph for all
operators. Previously the code assumed all operators only had
a single input except for the "Sum" operator.
This resolves issue seen when adding new operators that a subgraph
was incorrectly accepting a node when the subgraph should not have
because it was not following the topology of the nodes.
Signed-off-by: George Nash <george.nash@intel.com>