Debugger: Use correct path separators in display on Windows

Change-Id: Idef95d15bb78c7fbda8afac4f264e23011d63393
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Debugger: Don't make engine type appear editable

It is determined by the chosen debugger, no need for a combo box.

Change-Id: I1e278469bcd861a05eb102e94accee4dfc222b62
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>