reduce unnecessary logging during speedtest (#14387)

- speedtest logs calls that were canceled
  spuriously, in situations where it should
  be ignored.

- all errors of interest are always sent back
  to the client there is no need to log them
  on the server console.

- PUT failures should negate the increments
  such that GET is not attempted on unsuccessful
  calls.

- do not attempt MRF on speedtest objects.

cmd/erasure-metadata-utils.go

@@ -67,6 +67,9 @@ func reduceErrs(errs []error, ignoredErrs []error) (maxCount int, maxErr error)
 // values of maximally occurring errors validated against a generic
 // quorum number that can be read or write quorum depending on usage.
 func reduceQuorumErrs(ctx context.Context, errs []error, ignoredErrs []error, quorum int, quorumErr error) error {
+	if contextCanceled(ctx) {
+		return context.Canceled
+	}
 	maxCount, maxErr := reduceErrs(errs, ignoredErrs)
 	if maxCount >= quorum {
 		return maxErr