qt5.*: use default SDK on Darwin (14.4)

pkgs/development/libraries/qt-5/modules/qtbase.nix

@@ -17,7 +17,6 @@
   python3,
   which,
   # darwin support
-  apple-sdk_14,
   xcbuild,
 
   dbus,
@@ -86,11 +85,6 @@ let
       "linux-generic-g++"
     else
       throw "Please add a qtPlatformCross entry for ${plat.config}";
-
-  # Per https://doc.qt.io/qt-5/macos.html#supported-versions: build SDK = 13.x or 14.x.
-  darwinVersionInputs = [
-    apple-sdk_14
-  ];
 in
 
 stdenv.mkDerivation (
@@ -153,7 +147,6 @@ stdenv.mkDerivation (
       ++ lib.optionals (!stdenv.hostPlatform.isDarwin) (
         lib.optional withLibinput libinput ++ lib.optional withGtk3 gtk3
       )
-      ++ lib.optional stdenv.hostPlatform.isDarwin darwinVersionInputs
       ++ lib.optional developerBuild gdb
       ++ lib.optional (cups != null) cups
       ++ lib.optional mysqlSupport libmysqlclient

pkgs/development/libraries/qt-5/qtModule.nix

@@ -3,7 +3,6 @@
   stdenv,
   buildPackages,
   mkDerivation,
-  apple-sdk_14,
   perl,
   qmake,
   patches,
@@ -29,12 +28,7 @@ mkDerivation (
     inherit pname version src;
     patches = (args.patches or [ ]) ++ (patches.${pname} or [ ]);
 
-    buildInputs =
-      args.buildInputs or [ ]
-      # Per https://doc.qt.io/qt-5/macos.html#supported-versions
-      ++ lib.optionals stdenv.hostPlatform.isDarwin [
-        apple-sdk_14
-      ];
+    buildInputs = args.buildInputs or [ ];
 
     nativeBuildInputs =
       (args.nativeBuildInputs or [ ])