There is no "reuse report" feature on the SonarQube python plugin so for now you can't prevent SonarQube to start a new pylint analysis.
I suggest you ask for the creation of a JIRA feature request on SonarQube user mailing list.
In the meantime you can try to use sonar.python.pylint
parameter to make SonarQube run pyflakes instead of pylint as it seems output report are compatible (at least for Hudson). But I can't assure it will work.