Fix for Bug 3671 - QEMU GDB stub listens on IPv6-only port on Windows 7
The connection string used by the GDB stub does not specify which
version of the Internet Protocol should be used by the port on
which it listens. On host platforms with IPv6 support, such as
Windows 7, this means that the stub listens on an IPv6-only port.
Since the GDB client uses IPv4, this means that the client cannot
connect to QEMU.