deprecate/remove global WORM mode (#9436)

global WORM mode is a complex piece for which
the time has passed, with the advent of S3 compatible
object locking and retention implementation global
WORM is sort of deprecated, this has been mentioned
in our documentation for some time, now the time
has come for this to go.

cmd/fs-v1.go

@@ -991,12 +991,6 @@ func (fs *FSObjects) putObject(ctx context.Context, bucket string, object string
 
 	// Entire object was written to the temp location, now it's safe to rename it to the actual location.
 	fsNSObjPath := pathJoin(fs.fsPath, bucket, object)
-	// Deny if WORM is enabled
-	if isWORMEnabled(bucket) {
-		if _, err := fsStatFile(ctx, fsNSObjPath); err == nil {
-			return ObjectInfo{}, ObjectAlreadyExists{Bucket: bucket, Object: object}
-		}
-	}
 	if err = fsRenameFile(ctx, fsTmpObjPath, fsNSObjPath); err != nil {
 		return ObjectInfo{}, toObjectErr(err, bucket, object)
 	}