Bring back "Back out the krb5-1.11-run_user_0.patch"
    
    This reverts commit 8a5a8d492cc94cccf9b1a5b55377485f00807b7d.
    
    Special-case /run/user/0, attempting to create it when resolving a
    directory cache below it fails due to ENOENT and we find that it doesn't
    already exist, either, before attempting to create the directory cache
    (maybe helping, maybe just making things more confusing for #961235).