Add QNX as a xplatform target in CI

Task-number: QTQAINFRA-686

Change-Id: Iaccc634c816d9b34921b27709b58c7c8fb5fc7fc
Reviewed-by: Sergio Ahumada <sahumada@blackberry.com>
Reviewed-by: Simo Fält <simo.falt@digia.com>