OSSL_HPKE_get_recommended_ikmelen
size_t OSSL_HPKE_get_recommended_ikmelen(OSSL_HPKE_SUITE suite);
ikmelen = OSSL_HPKE_get_recommended_ikmelen(g_suite);
if (!TEST_false(OSSL_HPKE_get_recommended_ikmelen(bad_suite)))