vp9/rate_ctrl_rtc: Improve get cyclic refresh data

A client of the vp9 rate controller needs to know whether the
segmentation is enabled and the size of delta_q. It is also nicer to
know the size of map. This CL changes the interface to achieve these.

Bug: b:259487065
Test: Build

Change-Id: If05854530f97e1430a7b97788910f277ab673a87
2 files changed