Factor out debug port detection in PlatformDebugLibIoPort. Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> Message-Id: <20200423095358.2518197-4-anthony.perard@citrix.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com>