media-libs/dav1d: Add new package with patched version

Upstream currently has a bug (see [0]) which hasn't been fixed, yet. A fix, however, was provided as a patch.

Since we might need this bugfix for an upcoming Broadcast event, this commit shall provide a patched version of dav1d with the bugfix applied.

Package-Manager: Portage-3.0.30, Repoman-3.0.3 Signed-off-by: Adrian Schollmeyer nex+b-g-o@nexadn.de