Unify error message in case curl/cpprestsdk are not present

MariaDB [test]> create or replace table t9 engine=connect table_type=JSON file_name='users.json' http='http://jsonplaceholder.typicode.com' uri='users' option_list='curl=0';

ERROR 1105 (HY000): Cannot access to curl nor casablanca

MariaDB [test]> create or replace table t9 engine=connect table_type=JSON file_name='users.json' http='http://jsonplaceholder.typicode.com' uri='users' option_list='curl=1';

ERROR 1105 (HY000): curl failed, errno =22