qtbase: Make some output references more explicit

pkgs/development/qtcreator/default.nix

@@ -32,7 +32,7 @@ stdenv.mkDerivation rec {
   installFlags = [ "INSTALL_ROOT=$(out)" ] ++ optional withDocumentation "install_docs";
 
   preBuild = optional withDocumentation ''
-    ln -s ${qtbase}/$qtDocPrefix $NIX_QT5_TMP/share
+    ln -s ${getLib qtbase}/$qtDocPrefix $NIX_QT5_TMP/share
   '';
 
   postInstall = ''

pkgs/games/qgo/default.nix

@@ -43,6 +43,6 @@ stdenv.mkDerivation rec {
     # libQt5XcbQpa is a platform plugin dependency and doesn't get linked
     patchelf --add-needed libQt5XcbQpa.so.5 $out/bin/qgo
     wrapProgram $out/bin/qgo \
-      --set QT_QPA_PLATFORM_PLUGIN_PATH "${qt56.qtbase}/lib/qt-5.6/plugins/platforms/"
+      --set QT_QPA_PLATFORM_PLUGIN_PATH "${stdenv.lib.getBin qt56.qtbase}/lib/qt-5.6/plugins/platforms/"
   '';
 }