See if we can avoid some model / layer pickle issues with the aa attr in ConvNormAct

Author: rwightman

timm/layers/conv_bn_act.py

@@ -82,7 +82,8 @@ def out_channels(self):
     def forward(self, x):
         x = self.conv(x)
         x = self.bn(x)
-        if self.aa is not None:
+        aa = getattr(self, 'aa', None)
+        if aa is not None:
             x = self.aa(x)
         return x