tdf#120920 Assertion failure when switching slide layouts with text entered

no need to call StartListening here, has already been done inside
SdPage::CreatePresObj

Change-Id: I590e51f7afeb336d562d3ad9ccc123f542897aae
Reviewed-on: https://gerrit.libreoffice.org/62689
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
diff --git a/sd/source/core/sdpage.cxx b/sd/source/core/sdpage.cxx
index dd59303..841ac68 100644
--- a/sd/source/core/sdpage.cxx
+++ b/sd/source/core/sdpage.cxx
@@ -2113,8 +2113,6 @@
                        if (pSubtitleSheet)
                            pOutlParaObj->ChangeStyleSheetName(SfxStyleFamily::Page, pSubtitleSheet->GetName(), pSheet->GetName());
                    }

                    pNewObj->StartListening(*pSheet);
                }
            }