selftests: bpf: fix duplicate selftests in cpumask_success.

The BPF cpumask selftests are currently run twice in
test_progs/cpumask.c, once by traversing cpumask_success_testcases, and
once by invoking RUN_TESTS(cpumask_success). Remove the invocation of
RUN_TESTS to properly run the selftests only once.

Now that the tests are run only through cpumask_success_testscases, add
to it the missing test_refcount_null_tracking testcase. Also remove the
__success annotation from it, since it is now loaded and invoked by the
runner.

Signed-off-by: Emil Tsalapatis (Meta) <[e-mail]>
Acked-by: Hou Tao <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Alexei Starovoitov <[e-mail]>

tools/testing/selftests/bpf/prog_tests/cpumask.c

···
 	"test_global_mask_nested_deep_rcu",
 	"test_global_mask_nested_deep_array_rcu",
 	"test_cpumask_weight",
+	"test_refcount_null_tracking",
 	"test_populate_reject_small_mask",
 	"test_populate_reject_unaligned",
 	"test_populate",
···
 		verify_success(cpumask_success_testcases[i]);
 	}
 
-	RUN_TESTS(cpumask_success);
 	RUN_TESTS(cpumask_failure);
 }

tools/testing/selftests/bpf/progs/cpumask_success.c

···
 }
 
 SEC("tp_btf/task_newtask")
-__success
 int BPF_PROG(test_refcount_null_tracking, struct task_struct *task, u64 clone_flags)
 {
 	struct bpf_cpumask *mask1, *mask2;