Continue processing packet if mindelta is undefined

I have a controller I would like to create a HID mapping for, which can send the same data repeatedly if you turn its knob in the same direction. I'm interested in scripting this so I don't want to just connect it to jog_touch/jog_wheel, which I think already handle this.

For callbacks, the HID parser seems to always check for values that have changed between packets, so most of my packets are ignored. What I'd like to do is explicitly set mindelta to `undefined` for this control, and then have my callbacks fire for every packet (even when no values have changed). If mindelta is 0 you'll still get the current behavior.

Here's an excerpt that should illustrate: https://gist.github.com/decklin/7e50cc3cd20eb087f006