qemu-doc: Update to use the new way of attaching USB devices

qemu-doc: Update to use the new way of attaching USB devices

The preferred way of adding USB devices is via "-device" and
"device_add" nowadays, so let's start to get rid of "-usbdevice"
and "usb_add" in the documentation. While we're at it, also
add the new USB devices there which have been added to QEMU
during the last years, and get rid of the old "vendorid" and
"productid" parameters of "-usbdevice serial" which have been
removed in QEMU version 0.14.0 already.

Reviewed-by: Markus Armbruster <[email protected]>
Signed-off-by: Thomas Huth <[email protected]>
Message-id: 1494256429[email protected]
Signed-off-by: Gerd Hoffmann <[email protected]>