Fix CDB detection for Windows SDK 8.1

Change-Id: Ia39b736acb8ee9d35a6ee213265c780249271c49
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
Debugger: Remove redundant condition

Change-Id: I8afac043c4d3f3314df1a93f7a9850167a8e23f6
Reviewed-by: hjk <hjk121@nokiamail.com>