QtIFW

Fix update with long version numbers

Update fails if version number is longer than 32bit int. Fixed so that the
value is converted to 64bit int instead so the int overflow will not happen.

Change-Id: If7ab57e89b155793e9fab3ba5dad9c734adc2234
Fixes: QTIFW-1310
Reviewed-by: Konstantin Podsvirov <konstantin@podsvirov.pro>
Reviewed-by: Samuli Piippo <samuli.piippo@qt.io>