This is very strange. I would think the system was previously connected to another device using Intel® WiDi and the profile is still there.
Just in case, here you have more information about Intel® WiDi:
No it has never been connected using WiDi.
This is a brand new PC set togehter by me.
Fresh install of windows 8.1.
Only and always connected to my LG TV through HDMI.
I downloaded an app to my Android phone to search for WiDi displays but none could be found.
Removing the HDMI-cable and plugging it in again makes the WiDi display go away.
This sounds very strange. I have not seen reports from other customers with issues like the one you have so I would say it is an isolated issue.
I recommend you reinstalling the graphics driver as troubleshooting step. Here you can get it:
If you have problems during the installation try these steps: