fix compiler warning about uninitialized variable


git-svn-id: https://gnunet.org/svn/gnunet@33800 140774ce-b5e7-0310-ab8b-a85725594a96
-const

git-svn-id: https://gnunet.org/svn/gnunet@33801 140774ce-b5e7-0310-ab8b-a85725594a96
-move struct def to where it is used

git-svn-id: https://gnunet.org/svn/gnunet@33802 140774ce-b5e7-0310-ab8b-a85725594a96
-indentation fixes

git-svn-id: https://gnunet.org/svn/gnunet@33803 140774ce-b5e7-0310-ab8b-a85725594a96