docs(mge/functional): update functional.batch_norm docstring

imperative/python/megengine/functional/nn.py

@@ -1194,6 +1194,13 @@ def batch_norm(
         eps: a value added to the denominator for numerical stability. Default: 1e-5
         inplace: whether to update ``running_mean`` and ``running_var``
             inplace or return new tensors. Default: True
+        compute_mode: When set to 'default', no special requirements will be
+            placed on the precision of intermediate results. When set to 'float32',
+            float32 would be used for accumulator and intermediate result, but only
+            effective when input and output are of float16 dtype.
+        param_dim: a value indicating in which format the parameters are.
+             Default: 'dim_1c11', which means NCHW format.
+             And 'dim_111c' means NHWC format.
     """
     if inp.ndim != 4:
         raise NotImplementedError("batch_norm for ndim != 4")