Eliminate a warning about svn_wc__conflict_description2_dup().

This function is a public function with a private name.  Shortly,
svn_wc_conflict_description3_t will be removed.  So I'm leaving
the svn_wc__conflict_description2_dup() as deprecated but replacing
it with a now appropriately named svn_wc_conflict_description2_dup().

* subversion/include/svn_wc.h
  (svn_wc_conflict_description2_dup): New function.
  (svn_wc__conflict_description2_dup): Adjust the comment appropriately.
  (svn_wc_conflict_description2_t): Adjust the name of the dup function to
    modify if you change this.

* subversion/libsvn_wc/util.c
  (svn_wc_conflict_description2_dup): Moved from deprecated.c and renamed
    from svn_wc__conflict_description2_dup().

* subversion/libsvn_wc/deprecated.c
  (svn_wc__conflict_description2_dup): New implementation that just wraps
    svn_wc_conflict_description2_dup().

* subversion/libsvn_wc/info.c
  (svn_wc_info_dup): Adjust caller.



git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1618883 13f79535-47bb-0310-9956-ffa450edef68