rgbds: 0.4.2 -> 0.5.1

This also changes the owner of the GitHub repository and the homepage
URL because the repository was moved to a different organisation (the
old GitHub repository now redirects to the new one).

Also, since upstream switched to GNU Bison[1], the comment about byacc
is no longer necessary.

[1] gbdev/rgbds#595

pkgs/development/compilers/rgbds/default.nix

@@ -1,23 +1,19 @@
 {lib, stdenv, fetchFromGitHub, bison, flex, pkg-config, libpng}:
 
-# TODO: byacc is the recommended parser generator but due to https://github.com/rednex/rgbds/issues/333
-# it does not work for the moment. We should switch back to byacc as soon as the fix is integrated
-# in a published version.
-
 stdenv.mkDerivation rec {
   pname = "rgbds";
-  version = "0.4.2";
+  version = "0.5.1";
   src = fetchFromGitHub {
-    owner = "rednex";
+    owner = "gbdev";
     repo = "rgbds";
     rev = "v${version}";
-    sha256 = "0lygj7jzjlq4w0mkiir7ycysrd1p1akyvzrppjcchja05mi8wy9p";
+    sha256 = "11b1hg2m2f60q5622rb0nxhrzzylsxjx0c8inbxifi6lvmj9ak4x";
   };
   nativeBuildInputs = [ bison flex pkg-config libpng ];
   installFlags = [ "PREFIX=\${out}" ];
 
   meta = with lib; {
-    homepage = "https://rednex.github.io/rgbds/";
+    homepage = "https://rgbds.gbdev.io/";
     description = "A free assembler/linker package for the Game Boy and Game Boy Color";
     license = licenses.mit;
     longDescription =