Short answer: it didn't. Star Wars: The Force Unleashed II launched in 2010 on PlayStation 3, Xbox 360, Wii, Windows PC, and iOS — but the Nintendo DS was left out entirely.
The original Force Unleashed (2008) did receive a DS version developed by N-Space. That port featured unique touch-screen mechanics and a different gameplay style tailored to the handheld. However, by the time the sequel arrived, the DS was winding down. Nintendo had already announced the 3DS, and publishers were shifting focus to newer hardware and home consoles.
If you're craving Force Unleashed on a Nintendo handheld, the first game remains your only official option. The sequel is strictly a console/PC affair.