kselftest: devices: Add board file for google,spherion

Add a list of devices expected to be probed on the google,spherion
machine.

Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>

tools/testing/selftests/devices/boards/google,spherion

+usb camera 1 ic=0e isc=01 ip=00
+usb bluetooth 1 ic=e0 isc=01 ip=01 in=00
+pci wifi 1 v=14c3 d=7961