prepare for upgrade

git-svn-id: svn://svn.dd-wrt.com/DD-WRT@23607 52c4871e-980c-0410-b1e0-e73912ce01f8
update pcre - 8.34

git-svn-id: svn://svn.dd-wrt.com/DD-WRT@23608 52c4871e-980c-0410-b1e0-e73912ce01f8
igmp snooping

git-svn-id: svn://svn.dd-wrt.com/DD-WRT@23609 52c4871e-980c-0410-b1e0-e73912ce01f8