Make sure limit is never negative
Make sure limit is never negative

There were some cases where a negative limit could be passed in. Which
would happily make the query explode.

This is just a quick hack to make sure it never is negative.

Signed-off-by: Roeland Jago Douma <982d370f7dc34a05b4abe8788f899578d515262d@famdouma.nl>

nextcloud/server,nextcloud/server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,nextcloud/server,andreas-p/nextcloud-server,nextcloud/server,andreas-p/nextcloud-server