You sure can... I just did this last night. I programmed mine to the snap roll switch (who uses that thing anyway?). It's my experience that I don't want the choke on anything but a temporary switch or you will eventually accidentally hit it (I have too).

Here's how... keep your choke servo plugged into the gear channel. Inhibit the gear channel in the radio. Use a spare P-Mix and mix the gear (5) with itself. Leave it at 0 offset. Select origin mix. Select SNP as POS 1 and leave all the rest as POS 0. Set values in POS 0 to -100 on top and + 100 on bottom (use the gear switch to toggle between the top and bottom values). Set values in POS 1 to + 100 on top and -100 on bottom (use the Snap Roll switch to access Pos 1 and use the Gear switch to toggle between top and bottom values). Set the Travel of the choke servo as desired from code 12.

With this setup the Snap roll switch will control the choke servo between open and closed and the position of the gear switch is irrelevant (won't affect servo at all). I am using the Gear switch to toggle between 2 different throttle curves.

Hope this helps.