Correct a typo

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1543376 13f79535-47bb-0310-9956-ffa450edef68
Followup to r1456457
Correct typo in the name of a private field

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1543383 13f79535-47bb-0310-9956-ffa450edef68