* Rebase & review comments addressed.

python/tvm/relay/op/transform.py

@@ -244,9 +244,15 @@ def where(condition, x, y):
     return _make.where(condition, x, y)
 
 
-def split(data, indices_or_sections, axis=None, equal_split=False):
+def split(data, indices_or_sections, axis=0, equal_split=False):
     """Split input tensor along axis by sections or indices.
 
+    With equal_split being true it splits input into indices_or_sections[0]
+    sections and axis dimension should be a multiple of sections.
+
+    Other wise indices_or_sections is a tuple indicating indices
+    where the input is split on given axis.
+
     Parameters
     ----------
     data : relay.Expr