qtdeclarative: revert "Patch for scrollbar regression"

This reverts commit 5530043. The change breaks the build of
qtquickcontrols. Fixes #96159.

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

@@ -1,4 +1,4 @@
-{ qtModule, lib, fetchpatch, python3, qtbase, qtsvg }:
+{ qtModule, lib, python3, qtbase, qtsvg }:
 
 with lib;
 
@@ -23,12 +23,4 @@ qtModule {
     "bin/qmlscene"
     "bin/qmltestrunner"
   ];
-  patches =
-    # https://mail.kde.org/pipermail/kde-distro-packagers/2020-June/000419.html
-    lib.optional (lib.versionAtLeast qtbase.version "5.14.2")
-      (fetchpatch {
-        url = "https://codereview.qt-project.org/gitweb?p=qt/qtdeclarative.git;a=patch;h=3e47ac319b0f53c43cc02a8356c2dec4f0daeef4";
-        sha256 = "0wvncg7047q73nm0svc6kb14sigwk7sc53r4778kn033aj0qqszj";
-        name = "qtdeclarative-QQuickItemView-fix-max-extent.patch";
-      });
 }