Remove a redundant check

err must be nil at that point.

This also un-indents the success case, so that
it proceeds as a straight-line code.

Signed-off-by: Miloslav Trmač <mitr@redhat.com>

storage/layers.go

@@ -813,7 +813,6 @@ func (r *layerStore) Put(id string, parentLayer *Layer, names []string, mountLab
 			return nil, -1, err
 		}
 	}
-	if err == nil {
 	layer = &Layer{
 		ID:                 id,
 		Parent:             parent,
@@ -894,7 +893,6 @@ func (r *layerStore) Put(id string, parentLayer *Layer, names []string, mountLab
 		return nil, -1, err
 	}
 	layer = copyLayer(layer)
-	}
 	return layer, size, err
 }