Debugger: Interrupt inferior via signal operation on Windows.

Task-number: QTCREATORBUG-10558

Change-Id: I5a27beca4601cae3b0de8f903a2cbc08ee801149
Reviewed-by: Robert Loehning <robert.loehning@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>