lib/sql: fix permissions for v2.0.0 on postgres

lib/sql: fix permissions for v2.0.0 on postgres

Some tables are no longer present, and others that are used by the web
interface and mail parser need access permissions added.

This change was required to get patchwork going on patchwork.ozlabs.org;
there may be other permissions required, that we haven't hit yet. So,
some review would be good here.

Also: it's unlikely that we need DELETE for the mail parser, but I'm not
confident enough to remove that at the moment.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Reviewed-by: Stephen Finucane <stephen@that.guru>