mariadb: bump to 10.2.x release

mariadb: bump to 10.2.x release

Bump to 10.2.x release series which has support for OpenSSL 1.1.x.

- libmariadbclient was replaced by libmaria
- libmaria uses LGPL, hence license info updated
- upstream disabled xtradb engine, innodb is now default (cannot be
  built as plugin anymore)
- complex charsets are now all included (size increase), as otherwise
  compile fails
- patches adapted/refreshed

Signed-off-by: Sebastian Kemper <[email protected]>