long_double_representation required changes for ppc64le archi

Changes required in this fonction for ppc64le to avoid error msg while build:
===
Traceback (most recent call last):
  File "setup.py", line 192, in <module>
    setup_package()
...
  File "numpy/core/setup_common.py", line 305, in long_double_representation
    raise ValueError("Unrecognized format (%s)" % saw)
ValueError: Unrecognized format (['001', '043', '105', '147', '211', '253', '315', '357', '000', '000', '000', '124', '064', '157', '235', '301', '000', '000', '000', '000', '000', '000', '000', '000', '376', '334', '272', '230', '166', '124', '062', '020'])
===

Signed-off-by: Michel Normand <normand@linux.vnet.ibm.com>