RFR: 8238241: Clean up problem list for JFR tests

[Erik Gahlin]

Hi,

Could I have a review of a fix that removes two tests from the problem list.

jdk/jfr/jmx/security/TestEnoughPermission.java was fixed by JDK-8236582 
and jdk/jfr/api/consumer/recordingstream/TestSetStartTime.java was fixed 
with the integration of Event Streaming.

Bug:
https://bugs.openjdk.java.net/browse/JDK-8238241

Webrev:
http://cr.openjdk.java.net/~egahlin/8238241/

Testing:
100 times (ongoing)

Thanks
Erik