Fix some uninitialized pointers in crypto

crypto.c:2748:9: warning: variable 'bn_prime' is used uninitialized whenever '||' condition is true [-Wsometimes-uninitialized]
    if (!get_bn_from_bin(env, argv[0], &bn_verifier)
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
crypto.c:2758:6: note: uninitialized use occurs here
        if (bn_prime) BN_free(bn_prime);
            ^~~~~~~~
crypto.c:2748:9: note: remove the '||' if its condition is always false
    if (!get_bn_from_bin(env, argv[0], &bn_verifier)
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
crypto: Avoid test_server crash 'no_answer_from_tc_supervisor'
crypto: Add more lazy_eval to avoid no_answer_from_tc_supervisor

Amendment to f1ebf482e1460d6146d55aa6cab00ab3e11f1741
Merge branch 'nox/crypto-uninitialized-vars' into maint

* nox/crypto-uninitialized-vars:
  Fix some uninitialized pointers in crypto

OTP-11510
Merge branch 'sverk/crypto-no_answer_from_tc_supervisor' into maint

* sverk/crypto-no_answer_from_tc_supervisor:
  crypto: Add more lazy_eval to avoid no_answer_from_tc_supervisor
Prepare release