treewide: cleanup procps uses

pkgs/development/compilers/rust/rustc.nix

@@ -1,5 +1,5 @@
 { stdenv, targetPackages
-, fetchurl, fetchgit, fetchzip, file, python2, tzdata, procps
+, fetchurl, fetchgit, fetchzip, file, python2, tzdata, ps
 , llvm, jemalloc, ncurses, darwin, rustPlatform, git, cmake, curl
 , which, libffi, gdb
 , version
@@ -19,8 +19,6 @@ let
   inherit (stdenv.lib) optional optionalString;
   inherit (darwin.apple_sdk.frameworks) Security;
 
-  procps = if stdenv.isDarwin then darwin.ps else args.procps;
-
   llvmShared = llvm.override { enableSharedLibraries = true; };
 
   target = builtins.replaceStrings [" "] [","] (builtins.toString targets);
@@ -127,7 +125,7 @@ stdenv.mkDerivation {
 
   # ps is needed for one of the test cases
   nativeBuildInputs =
-    [ file python2 procps rustPlatform.rust.rustc git cmake
+    [ file python2 ps rustPlatform.rust.rustc git cmake
       which libffi
     ]
     # Only needed for the debuginfo tests