Log Message:
svt-av1: update to 2.3.0.

## [2.3.0] - 2024-10-28

API updates
- Preset shift: M12/M13 mapped to M11, M7-M11 shifted one position down. API \ 
does not change, all presets from MR-M13 will still be accepted
- svt_av1_enc_get_packet API is now a blocking call for low-delay enforcing a \ 
picture in, picture out model
- --fast-decode range changed from 0-1 to 0-2 available on all presets
- Introducing a new definition of --lp being levels of parallelism with a new \ 
field in the config structure level_of_parallelism
- logical_processors will be deprecated in the 3.0 release

Encoder
- NEW FAST DECODE MODE - (!2280)
-  New fast-decode (2) to allow for an average AV1 software cycle reduction of \ 
25-50% vs fast-decode 0 with a 1-3% BD-Rate loss across the presets
-  Improved fast-decode (1) option to increase its AV1 software cycle reduction \ 
by ~10% while maintaining the same quality levels
- Improved --lp settings for high resolutions, with CRF gaining a ~4% \ 
improvement in speed and VBR gaining ~15% (!2323)
- Further Arm-based optimizations improving the efficiency of previously written \ 
Arm-neon implementations by an average of 30%. See below for more information on \ 
specific presets
- Address speed regressions for high resolutions first pass encode by tuning the \ 
threading parameters, with 1080p showing the biggest gains
- Enabled AVX512 by default in cmake allowing for ~2-4% speedup
- Enabled LTO by default if using a new enough compiler (!2288, !2305)
  - If LTO is a problem or causes one, it can be disabled by adding \ 
-DSVT_AV1_LTO=OFF to cmake to force it off.
  - Please report any issues that occur when using it.

Cleanup Build and bug fixes and documentation
- third_party: update safestringlib with applicable upstream changes
- Improved the unit test coverage for Arm-neon code
- Updated documentation

Arm Improvements

- Speed comparison was done against v2.2 on AWS Graviton4 instances with Clang 19.1.1
- `--lp 1` was used for all tests

Standard bitdepth (Bosphorus 1080p):

| Preset                        | Uplift |
|-------------------------------|--------|
| 0                             | 1.15x  |
| 1                             | 1.24x  |
| 2                             | 1.29x  |
| 3                             | 1.17x  |
| 4                             | 1.22x  |
| 5                             | 1.31x  |
| 6                             | 1.40x  |
| 7 (against 2.2 preset 8)      | 1.50x  |
| 8 (against 2.2 preset 9)      | 1.61x  |
| 9 (against 2.2 preset 10      | 1.31x  |
| 10 (against 2.2 preset 11 )   | 1.29x  |
| 11 (against 2.2 preset 12/13) | 1.24x  |

High bitdepth (Bosphorus 2160p):

| Preset                        | Uplift |
|-------------------------------|--------|
| 0                             | 1.18x  |
| 1                             | 1.19x  |
| 2                             | 1.16x  |
| 3                             | 1.27x  |
| 4                             | 1.33x  |
| 5                             | 1.27x  |
| 6                             | 1.33x  |
| 7 (against 2.2 preset 8)      | 1.35x  |
| 8 (against 2.2 preset 9)      | 1.82x  |
| 9 (against 2.2 preset 10)     | 1.95x  |
| 10 (against 2.2 preset 11)    | 1.40x  |
| 11 (against 2.2 preset 12/13) | 1.35x  |