backend: remove unused Location method

internal/backend/swift/swift.go

@@ -118,11 +118,6 @@ func (be *beSwift) Connections() uint {
 	return be.connections
 }
 
-// Location returns this backend's location (the container name).
-func (be *beSwift) Location() string {
-	return be.container
-}
-
 // Hasher may return a hash function for calculating a content hash for the backend
 func (be *beSwift) Hasher() hash.Hash {
 	return md5.New()