Why? I only see 3 options here.

#1 bitcoin devs did slip malware in the code, what do you expect them to do if you tell them you found it? Confess?
#2 bitcoin devs did not slip malware in the code, its a false positive. Contacting them is useless, because they cant change the situation. Contact the anti virus vendor instead.
#3 bitcoin devs did not slip malware in the code, its not a false positive. Verifiying you are downloading the real thing solves this without contacting anyone.