Debugger: Remove RemoteGdbProcess and RemotePlainGdbAdapter

Should be superseded by using a LocalAdapter variant with
(remote) DeviceProcess.

Change-Id: I9834105ff677bfe5ca527778e9795efc3b677393
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
Debugger: Merge {Abstract,Local}PlainAdapter to GdbPlainEngine

Change-Id: Idb2197e429df2fb166f042649d3e95e88c28203e
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
DeviceProcess: Add write(const QByteArray &) function

Change-Id: Ia8e00c354056b96b966e7cdb86e51f838e70e738
Reviewed-by: Christian Kandeler <christian.kandeler@digia.com>
Debugger: Silence warnings about unused test code

Change-Id: I1800a1b84fdd03278ccb2431fb66791269ea8991
Reviewed-by: hjk <hjk121@nokiamail.com>