* add infer_value for common math ops
* convert constant bool tensor to bool value

* do not infer value when encounter 0 as division

for while condition, do not unrool if condition is a tensor

1) A[B]=U
2) A[A>n]=U
    A.shape == B.shape
    U is a scalar or Tensor(size==1)
    B is Tensor(dtype=bool)
    n is a Number

Signed-off-by: candanzg <zhangshucheng@huawei.com>

fix pylint

use scalar_lt primitive directly

fix review

Signed-off-by: leonwanghui <leon.wanghui@huawei.com>