How to correctly reference a supervisor who in the meantime got a doctorate
FYI: I did not reference the name of my supervisor advisor at all in my industry-targeting resume.  I do realize this may be different in CV-land.
I personally wouldn't use any honorifics in the CV.  (Next you'll be asking about assistant versus full professor!)  Just convey the information, the name.  I would opt for FI, LN.  I.e. Advisor: D. Linger.  Keep it tight, man.