debian binary server packages depend on client library

To work around an issue with binary incompatibility witht he mariadbclient libraries, O tried to install the libmysqlclient libraries.

However, the prebuilt debian packages for mariadb make this impossible, as the server explicitly depends on the mariadbclient package, which conflicts with the libmysqlclient.

I think only the metapackage should depend on both server and client, otherwise it is impossible to install the mysql client (required by many programs) alongside the mariadb server.