Those are both legitimate files. They are part of the Norton Internet Security suite. See this page
in Symantec support where the files are mentioned as two of the Symantec Security Resonse AV (antivirus) engines.
I am not sure why Symantec chose to hide the files, but I understand why AVG antirootkit picked them up. Most rootkits are
hidden driver (.sys) files, but not all hidden driver files are malware.
Hope this puts your mind at ease.