MRF: Better detection of non stable disks (#12252)

MRF does not detect when a node is disconnected and reconnected quickly
this change will ensure that MRF is alerted by comparing the last disk
reconnection timestamp with the last MRF check time.

Signed-off-by: Anis Elleuch <anis@min.io>

Co-authored-by: Klaus Post <klauspost@gmail.com>

cmd/storage-rest-client.go

@@ -167,6 +167,11 @@ func (client *storageRESTClient) IsOnline() bool {
 	return client.restClient.IsOnline()
 }
 
+// LastConn - returns when the disk is seen to be connected the last time
+func (client *storageRESTClient) LastConn() time.Time {
+	return client.restClient.LastConn()
+}
+
 func (client *storageRESTClient) IsLocal() bool {
 	return false
 }