fdo#48440 fix import of RTF_PAGE between text frames

Normally such a page break is surrounded by text, and text() already
calls checkNeedPap(), but in case the whole paragraph contains a page
break only, we need it here as well.

(cherry picked from commit b70f74cb)

Conflicts:
	sw/qa/extras/rtfimport/rtfimport.cxx

Change-Id: I3961272d77c743e0e6da2d5052e57cec5f5937e7
Reviewed-on: https://gerrit.libreoffice.org/1965Reviewed-by: Michael Stahl <mstahl@redhat.com>
Tested-by: Michael Stahl <mstahl@redhat.com>

writerfilter/source/rtftok/rtfdocumentimpl.cxx

@@ -1829,6 +1829,7 @@ int RTFDocumentImpl::dispatchSymbol(RTFKeyword nKeyword)
                 }
                 else
                 {
+                    checkNeedPap();
                     sal_uInt8 sBreak[] = { 0xc };
                     Mapper().text(sBreak, 1);
                     if (!m_bNeedPap)