Followup to r22762, squashing two error leaks.
Followup to r22762, squashing two error leaks.

* subversion/libsvn_client/copy.c
  (svn_client_copy4, svn_client_move5): If we are retrying the copy or
    move because the target already exists, clear the original error
    first.  Also correct a comment typo.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion