Fix QTextCodec case-insensitive comparison while in a Turkish locale.
Fix QTextCodec case-insensitive comparison while in a Turkish locale.

In Turkish, lowercase('I') is 'ı', which means comparing "iso-8859-1"
to "ISO-8859-1" will fail.

Reviewed-by: Denis Dzyubenko

KDE/qt,radekp/qt,pruiz/wkhtmltopdf-qt,radekp/qt,radekp/qt,RLovelett/qt,RLovelett/qt,pruiz/wkhtmltopdf-qt,RLovelett/qt,RLovelett/qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,KDE/qt,radekp/qt,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,KDE/qt,igor-sfdc/qt-wk,radekp/qt,KDE/qt,KDE/qt,RLovelett/qt,radekp/qt,pruiz/wkhtmltopdf-qt,RLovelett/qt,radekp/qt,igor-sfdc/qt-wk,RLovelett/qt,RLovelett/qt,pruiz/wkhtmltopdf-qt,RLovelett/qt,igor-sfdc/qt-wk,RLovelett/qt,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,radekp/qt,KDE/qt,RLovelett/qt,pruiz/wkhtmltopdf-qt,KDE/qt,KDE/qt,igor-sfdc/qt-wk,radekp/qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,radekp/qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk