selftests: arm64: Fix and enable test for setting current VL in vec-syscfg

We had some test code for verifying that we can write the current VL via
the prctl() interface but the condition for the test was inverted which
wasn't noticed as it was never actually hooked up to the array of tests
we execute. Fix this.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210929151925.9601-4-broonie@kernel.orgSigned-off-by: Will Deacon <will@kernel.org>

tools/testing/selftests/arm64/fp/vec-syscfg.c

@@ -329,12 +329,9 @@ static void prctl_set_same(struct vec_data *data)
 		return;
 	}
 
-	if (cur_vl != data->rdvl())
-		ksft_test_result_pass("%s current VL is %d\n",
-				      data->name, ret);
-	else
-		ksft_test_result_fail("%s prctl() VL %d but RDVL is %d\n",
-				      data->name, ret, data->rdvl());
+	ksft_test_result(cur_vl == data->rdvl(),
+			 "%s set VL %d and have VL %d\n",
+			 data->name, cur_vl, data->rdvl());
 }
 
 /* Can we set a new VL for this process? */
@@ -555,6 +552,7 @@ static const test_type tests[] = {
 	proc_write_max,
 
 	prctl_get,
+	prctl_set_same,
 	prctl_set,
 	prctl_set_no_child,
 	prctl_set_for_child,