RFR: JDK-8161348 Several tools/jlink tests failed due to time out

[Andrey Nazarov]

Hi,
please review Jlink tests.

I’ve increased default timeout to 5 minutes and skip tests in “-Xcomp” VM mode.

CR: http://cr.openjdk.java.net/~anazarov/JDK-8161348/webrev.00/ 
<http://cr.openjdk.java.net/~anazarov/JDK-8161348/webrev.00/>
Bug: https://bugs.openjdk.java.net/browse/JDK-8161348 
<https://bugs.openjdk.java.net/browse/JDK-8161348>

—Andrei