Remove stray semicolon at global scope

Remove stray semicolon at global scope

The Sun Studio compiler complains about an empty declaration here.

Note for future historians:  This does not mean that this compiler is
still of current interest for anyone using PostgreSQL.  But we can let
this small fix be its parting gift.

Reviewed-by: Andres Freund <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: https://www.postgresql.org/message-id/flat/a0f817ee-fb86-483a-8a14-b6f7f5991b6e%40eisentraut.org