selftests/hid: skip tests with HID-BPF if udev-hid-bpf is not installed

udev-hid-bpf is still not installed everywhere, and we should probably
not assume it is installed automatically.

Link: https://lore.kernel.org/r/20240506143612.148031-1-bentiss@kernel.org


Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>