Improve reentrancy heuristic (remove FP)

slither/detectors/reentrancy/reentrancy_benign.py

@@ -30,6 +30,8 @@ class ReentrancyBenign(Reentrancy):
             for f in contract.functions_and_modifiers_not_inherited:
                 for node in f.nodes:
                     if node.context[self.KEY]['calls']:
+                        if not any(n!=node for n in node.context[self.KEY]['calls']):
+                            continue
                         read_then_written = []
                         for c in node.context[self.KEY]['calls']:
                             read_then_written += [v for v in node.context[self.KEY]['written']

slither/detectors/reentrancy/reentrancy_eth.py

@@ -31,6 +31,8 @@ class ReentrancyEth(Reentrancy):
             for f in contract.functions_and_modifiers_not_inherited:
                 for node in f.nodes:
                     if node.context[self.KEY]['calls'] and node.context[self.KEY]['send_eth']:
+                        if not any(n!=node for n in node.context[self.KEY]['send_eth']):
+                            continue
                         read_then_written = []
                         for c in node.context[self.KEY]['calls']:
                             if c == node: