VVC decoder implementation: RefPicPocList[0/1] construction.

This calculates the list of POCs for STRP/LTRP/ILRP, following the procedure as specified in VVC spec section 8.3.2. Decoder will use this in combination of num_active_ref_idx[0/1] to decide the final ref picture lists 0/1 by looking up DPB for available reference pictures, and initiate the process of adding back unavailable ref pictures to DPB when such condition is detected.

Refer to document at https://docs.google.com/document/d/1DhhuVXPJAiOpCqVvmYQiPeehIfZoEY4Rqlvs4D7sQa8/ for more details of this process.

TEST: All H.266 unit tests pass.

Bug: 1417910
Change-Id: Iba1a75fc2a71ccb5e8a1b1faf943cf051fa8d4de
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4532003
Commit-Queue: Jianlin Qiu <jianlin.qiu@intel.com>
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1153759}