RFR: JMC-4467: Reducing roundtrips required for enablement checking

[Marcus Hirt]

Hi all,

Please review this fix to optimize the checks for JFR enablement, and to 
optimize the checks for commercial features enablement for JDK 11+. 

Jira:  https://bugs.openjdk.java.net/browse/JMC-4467
Patch: http://cr.openjdk.java.net/~hirt/JMC-4467/webrev.0/

Kind regards,
Marcus