Update is_floating_point to handle bfloat16 (apache#7133)

* Add div_ and is_floating_point operators

* Add handling of exprs to op, update tests

* Properly handle bfloat16 in is_floating_point

* Revert test changes

* revert whitespace changes

python/tvm/relay/frontend/pytorch.py

@@ -2067,7 +2067,7 @@ def is_floating_point(self, inputs, input_types):
         else:
             input_type = input_types[0]
 
-        is_float = input_type in ["float32", "float64", "float16"]
+        is_float = input_type in ["float32", "float64", "float16", "bfloat16"]
         return _expr.const(is_float)
 
     # Operator mappings