tc-testing: fix tdc tests for 'bpf' action

tc-testing: fix tdc tests for 'bpf' action

- correct a typo in the value of 'matchPattern' of test 282d, potentially
 causing false negative
- allow errors when 'teardown' executes '$TC action flush action bpf' in
 test 282d, to fix false positive when it is run with act_bpf unloaded
- correct the value of 'matchPattern' in test e939, causing false positive
 in case the BPF JIT is enabled

Fixes: 950b63d4478d ("tc-testing: add selftests for 'bpf' action")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Lucas Bates <lucasb@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>