qa: filter rsyslog metrics in qa/359 correctly
qa: filter rsyslog metrics in qa/359 correctly

If rsyslog PMDA is installed but the local rsyslog daemon
is not setup with instrumentation enabled, we can see the
Try Again message for those metrics - filter 'em.

adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp