Add a void* user data parameter to DvrTrackingSensorsStart.

So that the client can pass a user data pointer to the callback.

Bug: 78173127
Test: Run dvr_tracking-test on device.
Change-Id: Id3e977069a5b9a9f2ad8316c61aee227ebdd6e34
(cherry picked from commit c3fc600b9ead16a39e589ce8e6f635204922b0a6)