Doc: Fix warnings about wrong snippet path or missing .pro file

Task-number: QTBUG-91147
Change-Id: I6a55b2b713dd70cf1cbb0b93a8d4152e175e2c4d
Reviewed-by: Topi Reiniö <topi.reinio@qt.io>

src/dbus/doc/snippets/snippets.pro

@@ -0,0 +1,3 @@
+#! [qmake_use]
+QT += dbus
+#! [qmake_use]

src/network/doc/src/qtnetwork.qdoc

@@ -43,7 +43,7 @@
 
     Add \c network to the \c QT variable:
 
-    \snippet doc/snippets/network/network.pro 0
+    \snippet network/network.pro 0
 
     \section1 Articles and Guides
 

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

@@ -78,7 +78,7 @@
     See also the \l {Build with CMake} overview.
 
     \include module-use.qdocinc building with qmake
-    \snippet snippets/snippets.pro qmake_use
+    \snippet snippets.pro qmake_use
 
     \section1 Module Evolution
     \l{Changes to Qt OpenGL} lists important changes in the module API

src/printsupport/doc/snippets/snippets.pro

@@ -0,0 +1,3 @@
+#! [qmake_use]
+QT += printsupport
+#! [qmake_use]

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

@@ -172,7 +172,7 @@
   See also the \l {Build with CMake} overview.
 
   \include module-use.qdocinc building with qmake
-  \snippet snippets/snippets.pro qmake_use
+  \snippet snippets.pro qmake_use
 
   \section1 Module Evolution
   \l{Changes to Qt Print Support} lists important changes in the module API

src/sql/doc/snippets/code/code.pro

@@ -0,0 +1,3 @@
+#! [qmake_use]
+QT += sql
+#! [qmake_use]

src/testlib/doc/snippets/code/code.pro

@@ -0,0 +1,3 @@
+#! [qmake_use]
+QT += testlib
+#! [qmake_use]

src/testlib/doc/snippets/code/doc_src_qtestlib.pro

@@ -0,0 +1,11 @@
+#! [1]
+QT += testlib
+#! [1]
+
+#! [2]
+CONFIG += testcase
+#! [2]
+
+#! [3]
+CONFIG += no_testcase_installs
+#! [3]

src/xml/doc/snippets/snippets.pro

@@ -0,0 +1,3 @@
+#! [qmake_use]
+QT += xml
+#! [qmake_use]