tdf#120703 PVS: fix possible buffer over-read when iterating string

V560 A part of conditional expression is always true: nStartPos < nLen.

Change-Id: I2ae8634bd656e857724615d5187a14bd087598eb
Reviewed-on: https://gerrit.libreoffice.org/63958
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>

linguistic/source/gciterator.cxx

@@ -167,8 +167,9 @@ static sal_Int32 lcl_SkipWhiteSpaces( const OUString &rText, sal_Int32 nStartPos
     sal_Int32 nRes = nStartPos;
     if (0 <= nStartPos && nStartPos < nLen)
     {
+        const sal_Unicode* const pEnd = rText.getStr() + nLen;
         const sal_Unicode *pText = rText.getStr() + nStartPos;
-        while (nStartPos < nLen && lcl_IsWhiteSpace( *pText ))
+        while (pText != pEnd && lcl_IsWhiteSpace(*pText))
             ++pText;
         nRes = pText - rText.getStr();
     }