Remove metaobject revisioning for QQuickScreenAttached

Attached property versioning is not currently fully supported. Initial
approach was to add the version tags and not enforce them until you
could version attached properties. However the QML engine is currently
erroring on this. Specific error example:
""Screen.onNameChanged" is not available due to component versioning "

Workaround recommended in the JIRA task is to just not version them,
until attached property versioning is fully implemented.

Task-number: QTBUG-35569
Change-Id: I5ded7eb223ec00f70d847b3fac09ec240d5d7901
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>