innodb_file_format=Barracuda is the default in MariaDB 10.2.
Do not set it, because the option will be removed in MariaDB 10.3.
Also, do not set innodb_file_per_table=1 because it is the default.
Note that MDEV-11828 should fix the test innodb.innodb-64k
already in 10.1.
Syntax. Server support. Test cases.
InnoDB bugfixes:
* don't mess around with system sprintf's, always use my_error() for errors.
* don't use InnoDB internal error codes where OS error codes are expected.
* don't say "file not found", when it was.
