selftests/bpf: Remove unused enums

The enums undef and bidi are not used. Remove them.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210122154725.22140-3-bjorn.topel@gmail.com

tools/testing/selftests/bpf/xdpxceiver.h

@@ -92,8 +92,6 @@ struct flow_vector {
 	enum fvector {
 		tx,
 		rx,
-		bidi,
-		undef,
 	} vector;
 };