linuxPackages.rtl88x2bu: switch to the new, maintained repo
linuxPackages.rtl88x2bu: switch to the new, maintained repo

The new repo has the same maintainer and is the continuation of the repo
used prior to this commit.

Closes #147053

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs