RFR 8061442: Update jdk/tools tests to remove check for the "jre" directory

[FELIX YANG]

Hi all,
    please review the fix for jdk/test/tools. It cleans up checking for 'jre' 
directory, which has been removed during Jigsaw M2.

Bug:
    https://bugs.openjdk.java.net/browse/JDK-8061442

Webrev:
    http://cr.openjdk.java.net/~xiaofeya/8061442/webrev.00/

Thanks,
Felix