daemon: getInspectData(): reduce cyclomatic complexity
daemon: getInspectData(): reduce cyclomatic complexity

Use an early return if looking up metadata fails.

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

konstruktoid/docker-upstream,moby/moby,cpuguy83/docker,jimjag/docker,Mokolea/docker,Ramzec/docker,jimjag/docker,Ramzec/docker,moul/docker,moby/moby,Mokolea/docker,moby/moby,cpuguy83/docker,moul/docker,mahak/docker,Ramzec/docker,konstruktoid/docker-upstream,thaJeztah/docker,mahak/docker,moul/docker,trebonian/docker,konstruktoid/docker-upstream,trebonian/docker,thaJeztah/docker,jimjag/docker,mahak/docker,thaJeztah/docker,cpuguy83/docker,moby/moby,trebonian/docker,Mokolea/docker,trebonian/docker,Ramzec/docker,cpuguy83/docker,Mokolea/docker,moul/docker,thaJeztah/docker,mahak/docker,jimjag/docker,konstruktoid/docker-upstream