ConnectSE: ODBC: do not throw an error on empty CATFUNC=Columns

drop table if exists t1;

create table t1 engine=connect table_type=odbc catfunc=columns 

connection='DSN=pgodbc' tabname='t3';

select * from t1;

If the table 't3' does not exist in the remote DSN, the SELECT
query returns an error:

ERROR 1296 (HY000): Got error 174 'No data found for table t3' from 

It should return an empty set.

It does not seem to be useful to send a warning (instead of the error) on every SELECT.
But sending a warning at CREATE TABLE time could probably be useful, to make
the user aware that there is no such table on the remoter data source.