RFR(XS): JDK-8055052: [TESTBUG] runtime/NMT/JcmdDetailDiff.java fails on Windows when there are no debug symbols available

[George Triantafillou]

Please review this test fix for 8055052.  The check for 
WB_NMTReserveMemory was removed from the test.

Webrev: 
http://cr.openjdk.java.net/~gtriantafill/8055052/webrev-00/webrev/ 
<http://cr.openjdk.java.net/%7Egtriantafill/8055052/webrev-00/webrev/>
Bug: https://bugs.openjdk.java.net/browse/JDK-8055052

The fix was tested locally on Windows.

Thanks.

-George