Fix BMC compatibility with Python 2.6
Fix BMC compatibility with Python 2.6

BMC would try to push a bytearray at unpack.  In
python 2.6, this does not work.  Explicitly denote
changing to bytes to be compatible with python 2.6

Change-Id: I1c919a0050cae9f90c50d89abb6a77774db81381

stackforge/pyghmi,openstack/pyghmi,openstack/pyghmi