Followup to r1505066, fix 3rd-party FS module loading.
Followup to r1505066, fix 3rd-party FS module loading.

* subversion/libsvn_fs/fs-loader.c
  (get_or_allocate_third): Initialize new struct element.
  (get_library_vtable): Fix loop for 3rd-party modules.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1601411 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion