Fix a bug which can corrupt mergeinfo when filtering self-referential mergeinfo.
Fix a bug which can corrupt mergeinfo when filtering self-referential
mergeinfo.

* subversion/libsvn_client/merge.c
  (filter_self_referential_mergeinfo): When processing the array of
  svn_prop_t's *don't* create multiple elements for svn:mergeinfo.
  At most only one will be in the input array and at most only one should
  be in the output array.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@870541 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion