[INTERNAL] corrected defect in SMACK API

The error code from stream:error was not parsed correctly.

Change-Id: Ie0739903bbd85f2c05e76842f1545dbb45e334b2
Reviewed-on: http://saros-build.imp.fu-berlin.de/gerrit/1127
Tested-by: Jenkins CI
Reviewed-by: Stefan Rossbach <srossbach@arcor.de>