Deprecate Conv2d, ConvTranspose2d and BatchNorm2d (#2244)

* Deprecate Conv2d, ConvTranspose2d and BatchNorm

* Fix lint

torchvision/ops/misc.py

@@ -18,6 +18,30 @@
 from torchvision.ops import _new_empty_tensor
 
 
+class Conv2d(torch.nn.Conv2d):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        warnings.warn(
+            "torchvision.ops.misc.Conv2d is deprecated and will be "
+            "removed in future versions, use torch.nn.Conv2d instead.", FutureWarning)
+
+
+class ConvTranspose2d(torch.nn.ConvTranspose2d):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        warnings.warn(
+            "torchvision.ops.misc.ConvTranspose2d is deprecated and will be "
+            "removed in future versions, use torch.nn.ConvTranspose2d instead.", FutureWarning)
+
+
+class BatchNorm2d(torch.nn.BatchNorm2d):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        warnings.warn(
+            "torchvision.ops.misc.BatchNorm2d is deprecated and will be "
+            "removed in future versions, use torch.nn.BatchNorm2d instead.", FutureWarning)
+
+
 def _check_size_scale_factor(dim, size, scale_factor):
     # type: (int, Optional[List[int]], Optional[float]) -> None
     if size is None and scale_factor is None: