panfrost: Rotate trace files
When we trace the command stream with PAN_MESA_DEBUG=trace
and pandecode, rather than dumping everything to stdout and redirecting, ideally we would dump to a configurable file. Part 1 of this issue is setting up pandecode to take a FILE* for dumping instead of forcing stdout. Part 2 is rotating the trace file once per frame, so a directory of trace is produced instead of a single massive file, for easier analysis.
For bonus dump the framebuffer after each frame and then generate an HTML template to view traces and framebuffers over time Kidding. Probably.