Update Biff8.php

Author: oleibman

src/PhpSpreadsheet/Reader/Xls/Biff8.php

@@ -340,7 +340,7 @@ protected static function readBIFF8CellRangeAddressB(string $subData, string $ba
             $lc = '$' . $lc;
         } else {
             // column offset
-            // offset: 6; size: 2; first column with relative/absolute flags
+            // offset: 6; size: 2; last column with relative/absolute flags
             // bit: 7-0; mask 0x00FF; column index
             $relativeLcIndex = 0x00FF & self::getInt2d($subData, 6);
             $lcIndex = $baseCol + $relativeLcIndex;