multimedia/svt-av1: update to 1.2.1
Changes: https://gitlab.com/AOMediaCodec/SVT-AV1/-/releases/v1.2.0
Changes: https://gitlab.com/AOMediaCodec/SVT-AV1/-/releases/v1.2.1
(cherry picked from commit 7d7c819ad05eb854a2024db3844855e979e619b2)
(cherry picked from commit 6fbf0a3f11cba0f4011dc9942ddd7759f59c48b5)
(cherry picked from commit 9a8f68bf510118c11a8327520c052527e2d214f3)