tdf#109120 tdf#117212 count letters starting with 1

Count the merged letters starting with 1 again
instead of the record range numbers (regression from
commit ec44f87d5b99a3299322d0b79abc4c6808877865
"tdf#117212 sw mailmerge: merge only the selected range").

Show correct number in the message "Letter n" (follow-up
of commit 29db6427ea6e3f24fbacfd6ac053231106518749
"tdf#109120 : Mailmerge filenames starting with 1 (one)",
which fixed the numbers only in the file names, but
not in the message text of the status window.)

Change-Id: I28b9a00f9bc3e6db35f91de6dcd062e5f1c7444e
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/113407
Tested-by: Jenkins
Reviewed-by: László Németh <nemeth@numbertext.org>
diff --git a/sw/source/ui/dbui/mmresultdialogs.cxx b/sw/source/ui/dbui/mmresultdialogs.cxx
index 2c9d890..d726c1c 100644
--- a/sw/source/ui/dbui/mmresultdialogs.cxx
+++ b/sw/source/ui/dbui/mmresultdialogs.cxx
@@ -655,7 +655,7 @@ IMPL_LINK_NOARG(SwMMResultSaveDialog, SaveOutputHdl_Impl, weld::Button&, void)
                sExtension = pSfxFlt->GetWildcard().getGlob().getToken(1, '.');
                sPath += "." + sExtension;
            }
            OUString sStat = SwResId(STR_STATSTR_LETTER) + " " + OUString::number(nBegin + nDoc);
            OUString sStat = SwResId(STR_STATSTR_LETTER) + " " + OUString::number(nDoc + 1);
            xSaveMonitor->m_xPrintInfo->set_label(sStat);

            //now extract a document from the target document
@@ -683,7 +683,7 @@ IMPL_LINK_NOARG(SwMMResultSaveDialog, SaveOutputHdl_Impl, weld::Button&, void)
            pTargetView->GetWrtShell().EndAction();
            //then save it
            OUString sOutPath = aURL.GetMainURL(INetURLObject::DecodeMechanism::ToIUri);
            OUString sCounter = "_" + OUString::number(nBegin + nDoc + 1);
            OUString sCounter = "_" + OUString::number(nDoc + 1);
            sOutPath = sOutPath.replaceAt( sOutPath.getLength() - sExtension.getLength() - 1, 0, sCounter);

            while(true)