Bug #64172 errorInfo is not properly cleaned up

[kalaspuffar]

Added a check to see if the error code is PDO_ERR_NONE then we don't ask for more error information.

• Check if the SQLSTATE error code is equal to PDO_ERR_NONE before we ask the driver. And if no error is reported skip the extra call to the driver.
• Added a test to check that errorInfo is not filled with the old statement error message.
• Changed pdo_mysql/rests/pdo_mysql_stmt_errorinfo.phpt so It checks for NULL values when SQLSTATE error code is PDO_ERR_NONE so we follow manual page for PDO::errorInfo()

[kalaspuffar]

Tested with:

DSN sqlite - sqlite memory database
DSN mysql - mysql database locally
DSN pgsql - postgresql database locally
DSN odbc - db2 database locally
DSN firebird - firebird database locally
DSN oci - oracle database locally
DSN dblib - mssql database Amazon EC2

[smalyshev]

merged