x265: updated to 3.6

Version 3.6
===========

Release date - 4th April, 2024.

New feature
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1. Segment based Ratecontrol (SBRC) feature
2. Motion-Compensated Spatio-Temporal Filtering
3. Scene-cut aware qp - BBAQ (Bidirectional Boundary Aware Quantization)
4. Histogram-Based Scene Change Detection
5. Film-Grain characteristics as a SEI message to support Film Grain Synthesis(FGS)
6. Add temporal layer implementation(Hierarchical B-frame implementation)

Enhancements to existing features
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1. Added Dolby Vision 8.4 Profile Support

API changes
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1. Add Segment based Ratecontrol(SBRC) feature: "--[no-]sbrc".
2. Add command line parameter for mcstf feature: "--[no-]mctf".
3. Add command line parameters for the scene cut aware qp feature: "--scenecut-aware-qp" and "--masking-strength".
4. Add command line parameters for Histogram-Based Scene Change Detection: "--hist-scenecut".
5. Add film grain characteristics as a SEI message to the bitstream: "--film-grain <filename>"
6. cli: add new option --cra-nal (Force nal type to CRA to all frames expect for the first frame, works only with keyint 1)

Optimizations
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ARM64 NEON optimizations:- Several time-consuming C functions have been optimized for the targeted platform - aarch64. The overall performance increased by around 20%.
SVE/SVE2 optimizations

Bug fixes
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1. Linux bug to utilize all the cores
2. Crash with hist-scenecut build when source resolution is not multiple of minCuSize
3. 32bit and 64bit builds generation for ARM
4. bugs in zonefile feature (Reflect Zonefile Parameters inside Lookahead, extra IDR issue, Avg I Slice QP value issue etc..)
5. Add x86 ASM implementation for subsampling luma
6. Fix for abrladder segfault with load reuse level 1
7. Reorder miniGOP based on temporal layer hierarchy and add support for more B frame
8. Add MacOS aarch64 build support
9. Fix boundary condition issue for Gaussian filter

(adam)