How to remove bios from game lists?

[Stormrider]

I think I did it before but now I don't remember. I can edit my gamelist and chose the option remove from selection, but there I see the bios option greyd out.

[mr_doles]

I am sure there is a better or easier way to do this but this is what I did.  I created a bios folder under mame and put the bios files in there.  I edited the mame.ini rom path to read
rompath      roms;bios;chd
Then in mala I point the rom path to the rom folder.
You will notice I also moved the chd files out of the rom folder as well.