Fix missing argument

After the `residual_block` function was added an extra argument,
the call to it on line 145 wasn't updated.

Author: abiro

srgan/srgan.py

@@ -142,7 +142,7 @@ def deconv2d(layer_input):
         c1 = Activation('relu')(c1)
 
         # Propogate through residual blocks
-        r = residual_block(c1)
+        r = residual_block(c1, self.gf)
         for _ in range(self.n_residual_blocks - 1):
             r = residual_block(r, self.gf)