RFR: 8197589: CPU count wrong when both cpu shares and quotas are used

[Bob Vandette]

Please review this change to the cpu count selection logic used when running in docker containers.

BUG:

https://bugs.openjdk.java.net/browse/JDK-8197589

WEBREV:

http://bussund0417.us.oracle.com/export/users/bobv/jdk11hs/open/webrev/

The algorithm implemented in JDK-8146115 for selecting the number of active cpus assumed that a container 
would not be configured to use both cpu shares AND cpu quotas at the same time. This was an invalid assumption 
since this how containers are configured to allow bursting activity [1].  A Java process running in a container with 
cpu shares set to the equivalent of 2 cpus and a quota set to 6, will end up configuring the VM for 2 CPUs rather 
than 6.

[1] https://kubernetes.io/docs/tasks/configure-pod-container/assign-cpu-resource/#motivation-for-cpu-requests-and-limits

Bob.