If you're talking about just the latch part of the handle, someone's already made a custom latch for the 15-22, search the forums.
If you mean to modify an entire AR-15 charging handle, it's not going to work.
The 15-22 charging handle is considerably shorter than an AR-15 handle and has a solid front vs. the AR-15's hole for the gas tube. The AR-15 handle is also flared out in the middle where it fits into the slot in the upper. I don't think you can just cut the end off an AR-15 handle and still have it catch the nub on top of the 15-22 bolt. I'm also not sure what kind of differences there are where the latch connects with the upper as I've never tried swapping my rifle latches.
Has your 15-22 charging handle broken or given you problems? I'm sure that S&W would replace it if you called them.