Bugfix for 906929

Changed the syntax of request paramter "NoDevice" to comply with AWS EC2 API reference for RegisterImage and RunInstances.
Links to AWS EC2 API reference:
http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-RunInstances.html,
http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-RegisterImage.html
Link to the bug: https://bugzilla.redhat.com/show_bug.cgi?id=906929