Fix up unprivileged test case results for 'Dest pointer in r0' verifier tests
given they now need to reject R0 containing a pointer value, and add a couple
of new related ones with 32bit cmpxchg as well.

  root@foo:~/bpf/tools/testing/selftests/bpf# ./test_verifier
  #0/u invalid and of negative number OK
  #0/p invalid and of negative number OK
  [...]
  #1268/p XDP pkt read, pkt_meta' <= pkt_data, bad access 1 OK
  #1269/p XDP pkt read, pkt_meta' <= pkt_data, bad access 2 OK
  #1270/p XDP pkt read, pkt_data <= pkt_meta', good access OK
  #1271/p XDP pkt read, pkt_data <= pkt_meta', bad access 1 OK
  #1272/p XDP pkt read, pkt_data <= pkt_meta', bad access 2 OK
  Summary: 1900 PASSED, 0 SKIPPED, 0 FAILED
Acked-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>