set availableSpace to 0 if userFolder not found
set availableSpace to 0 if userFolder not found

Signed-off-by: Felix Nieuwenhuizen <9c69098d379350e157eff4ad93150662007b8fb2@tdlrali.com>

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