RFR (XS): 8198539: Cleanup of unused imports in java/util/jar/Attributes.java (java.base) and JdpController.java (jdk.management.agent)

[Langer, Christoph]

Hi,

please review a simple import cleanup fix for java/util/jar/Attributes.java and 
sun/management/jdp/JdpController.java.

Bug: https://bugs.openjdk.java.net/browse/JDK-8198539
Webrev: http://cr.openjdk.java.net/~clanger/webrevs/8198539.0/

Thanks and best regards
Christoph