scylladb: remove the "broken" mark, add "big-parallel"

The build is really CPU-intensive, and requires around
2 * --cores GiB RAM.

pkgs/servers/scylladb/default.nix

@@ -95,6 +95,6 @@ gcc8Stdenv.mkDerivation {
     license = licenses.agpl3;
     platforms = stdenv.lib.platforms.linux;
     maintainers = [ stdenv.lib.maintainers.farlion ];
-    broken = true;
+    requiredSystemFeatures = [ "big-parallel" ];
   };
 }

pkgs/top-level/all-packages.nix

@@ -24494,8 +24494,8 @@ in
   sct = callPackage ../tools/X11/sct {};
 
   scylladb = callPackage ../servers/scylladb {
-   thrift = thrift-0_10;
-   };
+    thrift = thrift-0_10;
+  };
 
   seafile-shared = callPackage ../misc/seafile-shared { };