we also take this opportunity to enforce that all the
directory creations actually succeed (there really
is no reason why that could fail though)
Test: TreeHugger, manually inspected /sys/fs/bpf contents on cuttlefish
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Icd7c1e6eba5736a58cf81476ddafc70df2807dd4