flake8 check: H233 the print operator

[Kui Shi]

As the H233 checking is added into Python package "hacking", the print operator problem is exposed.

Update the print operator to meet this check.

Details of H233:
in hacking Python package: core.py

@flake8ext
def hacking_python3x_print_function(logical_line):
    r"""Check that all occurrences look like print functions, not
        print operator.

    As of Python 3.x, the print operator has been removed.

    Okay: print(msg)
    Okay: print (msg)
    H233: print msg
    H233: print >>sys.stderr, "hello"
    H233: print msg,
    """

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/42287

[Kui Shi (skuicloud)]

duplicated with https://review.openstack.org/#/c/41549/