QtScript: Another crash fix on PowerPC
QtScript: Another crash fix on PowerPC

on 32bit PowerPC, the integer value and the pointer value are not
in the same word leading to crash.  So blindly casting between them
lead to crashes.

Use the new Register::withInt instead

Reviewed-by: Kent Hansen
(cherry picked from commit c8d2160f3aa9b6709874c9cf4a634a46728d6cc6)

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