in your agent policy, do you have it enabled to prompt for if restart is needed? Do these messages correspond to any update or deployment task running on the system? I would suggest opening a ticket with McAfee support to investigate, unless you can identify a specific task or point product update that may be triggering it.
Do you use McAfee HIPS? if so look for a file called in the Windows directory... think it's called HIPS_Reboot. If so delete this and reboot your device.