libaom uses the quantizer as an index for an array of size 64, so
encoder_settings_.qpMax must be <= 63.
Add a comment to LibaomAv1Encoder::SetSvcParams() to explain why the
method doesn't initialize svc_params.layer_target_bitrate.
Bug: None
Change-Id: I26be80de005752214365abbe8b9b32dc976cee0b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/293680
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Commit-Queue: Wan-Teh Chang <wtc@google.com>
Cr-Commit-Position: refs/heads/main@{#39572}
8f29b42670