In Major League Baseball, any player can play any position. This seems to be the main reason a Pitcher is suspended with the same standard suspension as a position player. This despite a pitcher’s suspension not being as likely to affect the team as perhaps a position player’s suspension would.
As far as I am aware, there is no provision in the CBA or official rules that allows for a player to be banned from playing a specific position. It’s either they are suspended, or they aren’t.