Checkmk Werk 7496: mem.linux: Prevent from crashing due to missing Slab data

ID: 7496 Title: mem.linux: Prevent from crashing due to missing Slab data Component: Checks & agents Level: 1 Class: Bug fix Version: 1.6.0i1 It is known that agent output may lack information about SReclaimable (Part of Slab, that might be reclaimed, such as caches) and Slab which lead to a crash of the check. This werk fixes this issue.