I can confirm this bug. Using qemu/kvm with autopkgtests I have keyboard-configuration 1.221 inside the testbed and the postinst script of keyboard-configuration fails with
cat: '/sys/bus/usb/devices/*:*/bInterfaceClass': No such file or directory cat: '/sys/bus/usb/devices/*:*/bInterfaceSubClass': No such file or directory cat: '/sys/bus/usb/devices/*:*/bInterfaceProtocol': No such file or directory -- regards Thomas
