Fix mailing address in README.

Task-number: QTBUG-32390
Change-Id: Ia3a45897b0b7a6bb2434297b21c45bf2dbdda0a5
Reviewed-by: Laszlo Papp <lpapp@kde.org>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
Merge remote-tracking branch 'origin/release' into stable

Change-Id: Ia8faa0ddd3672458d6daf6125cd629eaa46f6e8f