coverity#704348 Logically dead code

Change-Id: I8c97042c07e3eb66468591fa9c486998ffb1e37f
Reviewed-on: https://gerrit.libreoffice.org/3048Reviewed-by: Thomas Arnhold <thomas@arnhold.org>
Reviewed-by: Christoph Brill <egore911@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.cz>
Tested-by: Petr Mladek <pmladek@suse.cz>

sw/source/core/doc/doc.cxx

@@ -2473,6 +2473,7 @@ bool SwDoc::ConvertFieldsToText()
                     aPam2.SetMark();
                     aPam2.Move();
                     DeleteAndJoin(aPam2);//remove the field
+                    bRet=true;
                 }
             }
             ++aBegin;