MDEV-9466 : Exception handler on Windows does not output any text, if mysqld runs as service
MDEV-9466 : Exception handler on Windows does not output any text,
if mysqld runs as service

The bug is caused by the attempt to write to filedescriptor 2
(STDERR_FILENO), however in case of a service stderr has different fd
(debugging shows fileno(stderr) is 4 after freopen, and -1 before it)

Fixed definition of STDERR_FILENO for Windows to be fileno(stderr).

natsys/mariadb_10.2,ollie314/server,natsys/mariadb_10.2,flynn1973/mariadb-aix,flynn1973/mariadb-aix,natsys/mariadb_10.2,ollie314/server,natsys/mariadb_10.2,natsys/mariadb_10.2,ollie314/server,flynn1973/mariadb-aix,flynn1973/mariadb-aix,flynn1973/mariadb-aix,flynn1973/mariadb-aix,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,flynn1973/mariadb-aix,ollie314/server,flynn1973/mariadb-aix,ollie314/server,ollie314/server,ollie314/server,natsys/mariadb_10.2,ollie314/server,ollie314/server,flynn1973/mariadb-aix,natsys/mariadb_10.2,natsys/mariadb_10.2,slanterns/server,ollie314/server,flynn1973/mariadb-aix,flynn1973/mariadb-aix,ollie314/server