linux: Fix udev ID_PATH parsing for udl devices

The ID_PATH for a udl device looks like this:

  $ udevadm info /dev/dri/card2 | grep -w ID_PATH
  E: ID_PATH=pci-0000:00:14.0-usb-0:9.1:1.0

The parsing added in 0816e8fc ("linux: Make platform device probe
less fragile"), sets OdevAttributes::busid to "pci:0000:00:14.0", where
drmGetBusid() would have returned "3-9.1:1.0".

Identifying this as a "pci:*" device eventually causes the vendor/device
id check in probeSingleDevice() to fail, because a USB controller isn't
a supported device:

  $ udevadm info --path=/devices/pci0000:00/0000:00:14.0 | grep -e VENDOR -e ID_PCI_CLASS
  E: ID_PCI_CLASS_FROM_DATABASE=Serial bus controller
  E: ID_VENDOR_FROM_DATABASE=Intel Corporation

Instead of parsing out "pci:0000:00:14.0" in this case, use
"usb:0:9.1:1.0" so the device probe will succeed.

Fixes: 0816e8fc ("linux: Make platform device probe less fragile")
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
3 jobs for udl in 8 minutes and 15 seconds (queued for 1 minute and 7 seconds)
latest
Status Job ID Name Coverage
  Docker Image
passed #477206
debian-testing

00:00:19

 
  Build And Test
passed #477207
autotools-build-and-test

00:06:45

passed #477208
meson-build-and-test

00:01:10