tdf#156286 sc: fix crash with column deletion

Skip negative indices, which caused the crash, when
more columns were deleted, than the remaining columns
before them.

Regression from commit dd8e061406fac581d399da088c7f0187278035dc
"tdf#153437 sc: fix broken formatting without performance regression".

Change-Id: I223e2fbb321fc4bd2ddb7a67a16a64c69e1e7872
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/154445
Reviewed-by: Czeber László <czeber.laszloadam@nisz.hu>
Tested-by: Jenkins
Tested-by: László Németh <nemeth@numbertext.org>
Reviewed-by: László Németh <nemeth@numbertext.org>
diff --git a/sc/source/core/data/table2.cxx b/sc/source/core/data/table2.cxx
index cb1316e..ab1516b 100644
--- a/sc/source/core/data/table2.cxx
+++ b/sc/source/core/data/table2.cxx
@@ -401,7 +401,7 @@ void ScTable::DeleteCol(
        for (SCCOL nCol = nStartCol + nSize; nCol < aCol.size(); ++nCol)
            aCol[nCol].SwapCol(aCol[nCol - nSize]);
        // When delete column(s), initialize the last columns from the default attributes
        for (SCCOL nCol = aCol.size() - nSize; nCol < aCol.size(); ++nCol)
        for (SCCOL nCol = aCol.size() < static_cast<SCCOL>(nSize) ? 0 : aCol.size() - nSize; nCol < aCol.size(); ++nCol)
            aCol[nCol].Init(nCol, aCol[nCol].GetTab(), rDocument, false);
    }
    else