pkgs/nixos-rebuild: fix typo

outputs.nix

@@ -38,6 +38,7 @@ self = {
           {
             config.nixpkgs.overlays = [
               ( import ./pkgs/overlays/selfExpr.nix { nixpkgsPath = "${builtins.toString ./.}/pkgs/top-level/impure.nix"; } )
+              ( import "${inputs.nixpkgs}/pkgs/top-level/by-name-overlay.nix" "${builtins.toString ./.}/pkgs/by-name" )
               self.overlays.versionInfoFixup
             ];
           }

pkgs/by-name/ni/nixos-rebuild/nixos-rebuild.sh

@@ -454,7 +454,7 @@ trap cleanup EXIT
 # Re-execute nixos-rebuild from the Nixpkgs tree.
 if [[ -z $_NIXOS_REBUILD_REEXEC && -n $canRun && -z $fast ]]; then
     if [[ -z $buildingAttribute ]]; then
-        p=$(runCmd nix-build --no-out-link $buildFile -A "${$attr:+$attr.}config.system.build.nixos-rebuild" "${extraBuildFlags[@]}")
+        p=$(runCmd nix-build --no-out-link $buildFile -A "${attr:+$attr.}config.system.build.nixos-rebuild" "${extraBuildFlags[@]}")
         SHOULD_REEXEC=1
     elif [[ -z $flake ]]; then
         if p=$(runCmd nix-build --no-out-link --expr 'with import <nixpkgs/nixos> {}; config.system.build.nixos-rebuild' "${extraBuildFlags[@]}"); then

pkgs/by-name/ni/nixos-rebuild/package.nix

@@ -12,7 +12,7 @@
 , installShellFiles
 }:
 let
-  fallback = import ./../../../../nixos/modules/installer/tools/nix-fallback-paths.nix;
+  fallback = import "${(import ../../../../inputs.nix {}).nixpkgs}/nixos/modules/installer/tools/nix-fallback-paths.nix";
 in
 substitute {
   name = "nixos-rebuild";