usb-host: hostaddr=0XX is parsed as octal number

when doing

device_add usb-host,hostaddr=010

taking 010 in the format of both lsusb or udev, qemu parses an octal number and assumes hostaddr=8.
(i used a 2.0 device on the ehci.0 bus)
at least to me that is confusing.

also:

when adding a non-existent usb device (bogus hostaddr), the following is created according to 'usb info':

  Device 1.0, Port 1, Speed 1.5 Mb/s, Product USB Host Device

in usb_qdev_init():
usb_claim_port is called but usb_device_init does not report an error and thus usb_release_port is not called.