This is a non-functional change, which intends to correct element
names of a tuple returned by Popen.communicate().
Both in python2 and python3 subprocess.Popen.communicate() method
returns a tuple (stdoutdata, stderrdata), thus old assignments and
collateral comments are incorrect from human's point of view, however
formally there is no error in the code.
The change is desired to have to avoid copy-paste errors in future.
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Ross Burton <ross.burton@intel.com>