nodedev_list: Adjust the usb_ exclude list

The current exclude list only removes "X-X:X-X" devices; however, if
there are "X-X.X:X-X" device it doesn't find them - thus adding to the
list of expected devices, which libvirt doesn't find resulting in a
test error.

Rather than figure out all the nuances, I adjusted the "X-X" to be just
any string before a ":X-X".

FWIW: Output had:
...
2-1.3
3-0:1.0
2-1.3:1.0
...
where ls -al /sys/bus/usb/devices has:

2-1.3 -> ../../../devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.3
2-1.3:1.0 -> ../../../devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.3/2-1.3:1.0