MFH: r508199
multimedia/dav1d: update to 0.4.0
- Drop meson hack for aarch64 after r50500
Changes: https://code.videolan.org/videolan/dav1d/tags/0.4.0
Changes: https://code.videolan.org/videolan/dav1d/blob/0.4.0/NEWS
Changes: https://code.videolan.org/videolan/dav1d/compare/0.3.1...0.4.0
Approved by: ports-secteam blanket (required by Firefox 69)