ossl_namemap_empty
nms = ossl_namemap_empty(namemap);
int ossl_namemap_empty(OSSL_NAMEMAP *namemap);
ok = TEST_int_eq(ossl_namemap_empty(NULL), 1)
&& TEST_int_eq(ossl_namemap_empty(nm), 1)
&& TEST_int_eq(ossl_namemap_empty(nm), 0);