re-enable enginepkcs11 system test

The enginepkcs11 test was accidentally disabled by a wrong prereq.sh condition in !5924 (2e9fd6d0).

Once enabled, the test has a couple of failures that need to be addressed:

2024-02-26 17:25:39 INFO:enginepkcs11.test_enginepkcs11     I:Test SOA is signed for ecdsap256sha256.same-policy.views in view1 (65)
2024-02-26 17:25:42 INFO:enginepkcs11.test_enginepkcs11     I:failed (SOA RRset not signed)
2024-02-26 17:25:42 INFO:enginepkcs11.test_enginepkcs11     I:Test DNSKEY is signed for ecdsap256sha256.same-policy.views in view1 (66)
2024-02-26 17:25:45 INFO:enginepkcs11.test_enginepkcs11     I:failed (DNSKEY RRset not signed)

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