Reviewing r1572120:
Simplify, as JK_HAVE_IPV6 in this case is defined several lines earlier.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/jk/trunk@1572359 13f79535-47bb-0310-9956-ffa450edef68
Update instruction following the changes in r1572035

git-svn-id: https://svn.apache.org/repos/asf/tomcat/jk/trunk@1572362 13f79535-47bb-0310-9956-ffa450edef68