Subversion: Allow empty commit message

Task-number: QTCREATORBUG-7151

Change-Id: I1607d7c61e33c36c35877d11edf821628a0db3ed
Reviewed-by: Tobias Hunger <tobias.hunger@nokia.com>

src/plugins/subversion/subversionsubmiteditor.cpp

@@ -43,6 +43,7 @@ SubversionSubmitEditor::SubversionSubmitEditor(const VcsBase::VcsBaseSubmitEdito
     VcsBase::VcsBaseSubmitEditor(parameters, new Utils::SubmitEditorWidget(parentWidget))
 {
     setDisplayName(tr("Subversion Submit"));
+    setDescriptionMandatory(false);
 }
 
 void SubversionSubmitEditor::setStatusList(const QList<StatusFilePair> &statusOutput)