tdf#132097: fix Find Previous with direction columns crashes in specific case

See bt here:
https://bugs.documentfoundation.org/attachment.cgi?id=159553

nBlockPos vector is created with nLastCol + 1 elements,
so if we click on a cell in a column which is after last value,
the search will crash

Change-Id: I9de688a8a80a45c3e5ddea6d2f461926e9777052
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/92165
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
(cherry picked from commit 2670e980c7dbadbdc20ff23d57ad892951edc254)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/92296
Reviewed-by: Xisco FaulĂ­ <xiscofauli@libreoffice.org>
diff --git a/sc/source/core/data/table6.cxx b/sc/source/core/data/table6.cxx
index 4d09986..ecaf800 100644
--- a/sc/source/core/data/table6.cxx
+++ b/sc/source/core/data/table6.cxx
@@ -328,8 +328,8 @@ bool ScTable::Search(const SvxSearchItem& rSearchItem, SCCOL& rCol, SCROW& rRow,
    bool bSkipFiltered = !rSearchItem.IsSearchFiltered();
    bool bSearchNotes = (rSearchItem.GetCellType() == SvxSearchCellType::NOTE);
    // We need to cache sc::ColumnBlockConstPosition per each column.
    std::vector< sc::ColumnBlockConstPosition > blockPos( nLastCol + 1 );
    for( SCCOL i = 0; i <= nLastCol; ++i )
    std::vector< sc::ColumnBlockConstPosition > blockPos( nLastCol + 2 );
    for( SCCOL i = 0; i <= nLastCol+1; ++i )
        aCol[ i ].InitBlockPosition( blockPos[ i ] );
    if (!bAll && rSearchItem.GetBackward())
    {