Doc: Setting module pages' \qtvariable.

Argument to \qtvariable is the QT variable needed for linking to the
module.

Task-number: QTBUG-32172
Change-Id: I181c0cfaf9529f3aea741cdaee0f20d6cd0e2d2f
Reviewed-by: Martin Smith <martin.smith@digia.com>

src/concurrent/doc/src/qtconcurrent-module.qdoc

@@ -31,6 +31,7 @@
     \brief The Qt Concurrent module contains functionality to support concurrent execution of program code
 
     \ingroup modules
+    \qtvariable concurrent
 
     The Qt Concurrent module extends the basic threading support found in \l{Qt Core} module and
     simplifies the development of code that can be executed in parallel on all available CPU cores.

src/corelib/doc/src/qtcore.qdoc

@@ -29,6 +29,7 @@
     \module QtCore
     \title Qt Core C++ Classes
     \ingroup modules
+    \qtvariable core
 
     \brief Provides core non-GUI functionality.
 

src/dbus/doc/src/qtdbus-module.qdoc

@@ -32,6 +32,7 @@
     to perform Inter-Process Communication using the \l{D-Bus} protocol.
 
     \ingroup modules
+    \qtvariable dbus
 
     \target The QDBus compiler
 

src/gui/doc/src/qtgui.qdoc

@@ -29,6 +29,7 @@
     \module QtGui
     \title Qt GUI C++ Classes
     \ingroup modules
+    \qtvariable gui
 
     \brief The Qt GUI module provides the basic enablers for graphical
     applications written with Qt.

src/network/doc/src/qtnetwork.qdoc

@@ -65,6 +65,7 @@
     \module QtNetwork
     \title Qt Network C++ Classes
     \ingroup modules
+    \qtvariable network
     \brief Provides classes to make network programming easier and portable
 
     To include the definitions of the module's classes, use the

src/opengl/doc/src/qtopengl-module.qdoc

@@ -29,6 +29,7 @@
     \module QtOpenGL
     \title Qt OpenGL C++ Classes
     \ingroup modules
+    \qtvariable opengl
 
     \brief The Qt OpenGL module offers classes that make it easy to
     use OpenGL in Qt applications.

src/printsupport/doc/src/qtprintsupport-module.qdoc

@@ -31,6 +31,7 @@
     \brief The Qt PrintSupport module provides classes to make printing easier and portable.
 
     \ingroup modules
+    \qtvariable printsupport
 
     To include the definitions of the module's classes, use the
     following directive:

src/sql/doc/src/qtsql.qdoc

@@ -62,6 +62,7 @@
     \module QtSql
     \title Qt SQL C++ Classes
     \ingroup modules
+    \qtvariable sql
     \brief Provides a driver layer, SQL API layer, and a user
     interface layer for SQL databases.
 

src/testlib/doc/src/qttest.qdoc

@@ -29,6 +29,7 @@
     \module QtTest
     \title Qt Test C++ Classes
     \ingroup modules
+    \qtvariable testlib
 
     \keyword QtTest
 

src/widgets/doc/src/qtwidgets.qdoc

@@ -29,6 +29,7 @@
     \module QtWidgets
     \title Qt Widgets C++ Classes
     \ingroup modules
+    \qtvariable widgets
 
     \brief The Qt Widgets module extends Qt GUI with C++ widget functionality.
 

src/xml/doc/src/qtxml.qdoc

@@ -29,6 +29,7 @@
     \module QtXml
     \title Qt XML C++ Classes
     \ingroup modules
+    \qtvariable xml
 
     \brief The Qt XML module provides C++ implementations of the SAX and DOM standards for XML.