fix: make sure to avoid calling RenameData() on disconnected disks. (#14094)

Large clusters with multiple sets, or multi-pool setups at times might
fail and report unexpected "file not found" errors. This can become
a problem during startup sequence when some files need to be created
at multiple locations.

- This PR ensures that we nil the erasure writers such that they
  are skipped in RenameData() call.

- RenameData() doesn't need to "Access()" calls for `.minio.sys`
  folders they always exist.

- Make sure PutObject() never returns ObjectNotFound{} for any
  errors, make sure it always returns "WriteQuorum" when renameData()
  fails with ObjectNotFound{}. Return appropriate errors for all
  other cases.

cmd/erasure-encode.go

@@ -52,7 +52,10 @@ func (p *parallelWriter) Write(ctx context.Context, blocks [][]byte) error {
 			if p.errs[i] == nil {
 				if n != len(blocks[i]) {
 					p.errs[i] = io.ErrShortWrite
+					p.writers[i] = nil
 				}
+			} else {
+				p.writers[i] = nil
 			}
 		}(i)
 	}
@@ -93,6 +96,7 @@ func (e *Erasure) Encode(ctx context.Context, src io.Reader, writers []io.Writer
 		blocks, err = e.EncodeData(ctx, buf[:n])
 		if err != nil {
 			logger.LogIf(ctx, err)
+
 			return 0, err
 		}