Remove an unused parameter.

* subversion/libsvn_wc/wc_db.h
  (svn_wc__db_pristine_transfer): Remove the unused 'checksum' parameter.

* subversion/libsvn_wc/wc_db_pristine.c
  (pristine_transfer_txn2): Unconditionally find the checksum, as we know it
    is not passed in.
  (svn_wc__db_pristine_transfer): Remove the unused 'checksum' parameter.

* subversion/libsvn_wc/copy.c
  (copy_versioned_file): Adjust caller.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1428592 13f79535-47bb-0310-9956-ffa450edef68