RFR 8027058: sun/management/jmxremote/bootstrap/RmiBootstrapTest.sh Failed to initialize connector

[Jaroslav Bachorik]

Please, review the following test change:

Issue:  https://bugs.openjdk.java.net/browse/JDK-8027058
Webrev: http://cr.openjdk.java.net/~jbachorik/8027058/webrev.00

The test fails when the requested port is unavailable. The test logic 
already runs the subtests with different port numbers (increasing the 
port number for each subtest) and this patch adds the logic to increase 
the port number in case of the subtest failure caused by BindException. 
This way the test is able to "autodiscover" free ports and run the 
bootstrap subtests successfully.

Thanks,

-JB-