qGAN - PyTorch Discriminator Fix (qiskit-community/qiskit-aqua#1391)

* update pytorch discriminator

Co-authored-by: Steve Wood <40241007+woodsp-ibm@users.noreply.github.com>
Co-authored-by: woodsp <woodsp@us.ibm.com>

qiskit/aqua/components/neural_networks/pytorch_discriminator.py

@@ -90,7 +90,7 @@ def load_model(self, load_dir: str):
         Args:
             load_dir: file with stored pytorch discriminator model to be loaded
         """
-        torch.load(load_dir)
+        self._discriminator = torch.load(load_dir)
 
     @property
     def discriminator_net(self):