Doc: Add CMake to the "Resource System" documentation

Change-Id: I4c6a7cfb2f6351e9587d47ab6708d92a1a4e42a4
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
(cherry picked from commit 97228214bd63f37563669049bfa13d33efa97c48)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/corelib/doc/snippets/resource-system/CMakeLists.txt

@@ -0,0 +1,23 @@
+project(my_app)
+cmake_minimum_required(VERSION 3.16)
+find_package(Qt6 REQUIRED COMPONENTS Widgets)
+
+#! [AUTORCC]
+set(CMAKE_AUTORCC ON)
+
+qt_add_executable(my_app
+    application.qrc
+    mainwindow.cpp)
+#! [AUTORCC]
+
+#! [qt_add_resources]
+qt_add_resources(my_app "app_images"
+    PREFIX "/"
+    FILES
+        "images/copy.png"
+        "images/cut.png"
+        "images/new.png"
+        "images/open.png"
+        "images/paste.png"
+        "images/save.png")
+#! [qt_add_resources]

src/corelib/doc/src/resource-system.qdoc

@@ -38,7 +38,7 @@
     (icons, translation files, etc.) and you don't want to run the
     risk of losing the files.
 
-    The resource system is based on tight cooperation between \l qmake,
+    The resource system is based on tight cooperation between the build system,
     \l rcc (Qt's resource compiler), and QFile.
 
     \section1 Resource Collection Files (\c{.qrc})
@@ -122,9 +122,25 @@
 
     \section2 Compiled-In Resources
 
-    For a resource to be compiled into the binary the \c .qrc file must be
+    For a resource to be compiled into the binary, the \c .qrc file must be
-    mentioned in the application's \c .pro file so that \c qmake knows
+    mentioned in the application's project file so that the build tool knows
-    about it. For example:
+    about it.
+
+    In CMake projects, one can use CMake's built-in \c AUTORCC feature to add \c
+    .qrc files directly as source files:
+
+    \snippet resource-system/CMakeLists.txt AUTORCC
+
+    See \l {https://cmake.org/cmake/help/latest/prop_tgt/AUTORCC.html}
+    {CMake's AUTORCC documentation}.
+
+    Qt's own CMake function \l qt_add_resources allows more control over the
+    creation of resources. For example, it allows to specify the content of the
+    resource directly in the project file without writing a \c .qrc file first:
+
+    \snippet resource-system/CMakeLists.txt qt_add_resources
+
+    In qmake projects, assign the \c .qrc files to the \l RESOURCES variable:
 
     \snippet resource-system/application.pro 0