RFR(S): 8187066: -Xlog:help "=debug" example is not quite accurate

[Marcus Larsson]

Hi,

Please review the following trivial patch to change wording in 
-Xlog:help output regarding levels.

Issue:
https://bugs.openjdk.java.net/browse/JDK-8187066

Webrev:
http://cr.openjdk.java.net/~mlarsson/8187066/webrev.00

Thanks,
Marcus