pkg/system: create SecurityAttribute only once (Windows)
pkg/system: create SecurityAttribute only once (Windows)

The same attribute was generated for each path that was created, but always
the same, so instead of generating it in each iteration, generate it once,
and pass it to our mkdirall() implementation.

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>

konstruktoid/docker-upstream,jimjag/docker,konstruktoid/docker-upstream,trebonian/docker,jimjag/docker,thaJeztah/docker,Ramzec/docker,moby/moby,thaJeztah/docker,jimjag/docker,Mokolea/docker,trebonian/docker,mahak/docker,konstruktoid/docker-upstream,Mokolea/docker,trebonian/docker,Ramzec/docker,mahak/docker,Ramzec/docker,mahak/docker,moby/moby,moby/moby,moby/moby,trebonian/docker,jimjag/docker,thaJeztah/docker,Ramzec/docker,konstruktoid/docker-upstream,thaJeztah/docker,Mokolea/docker,Mokolea/docker,mahak/docker