Doc: Fix documentation warnings for Qt Gui

* Fix file quoting in RHI Window example
* Add missing \inmodule commands for QRhi Classes
* Add missing dependency to qtshadertools
* Remove documentation for non-existent overload of
  QRhiGraphicsPipeline::setTargetBlends()

Other fixed warnings:

src/gui/rhi/qrhi.cpp:
* warning: clang couldn't find function when parsing
  \fn void setUsage(UsageFlags u)
* warning: clang couldn't find function when parsing
  \fn virtual bool QRhiSwapChain::isFormatSuported(Format f)

Change-Id: I73ff7896c3d5c8bb491368e941b32c8026a47191
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

examples/gui/doc/src/rhiwindow.qdoc

@@ -220,8 +220,8 @@
     The QRhiSwapChain is associated with the QWindow and the depth/stencil
     buffer.
 
-    \snippet rhiwindow/rhiwindow.cpp swapchain-data
+    \snippet rhiwindow/rhiwindow.h swapchain-data
-
+    \codeline
     \snippet rhiwindow/rhiwindow.cpp swapchain-init
 
     When the window size changes, the swapchain needs to be resized as well.

src/gui/doc/qtgui.qdocconf

@@ -39,6 +39,7 @@ depends += \
     qtdoc \
     qmake \
     qtcmake \
+    qtshadertools \
     qttestlib \
     qtplatformintegration \
     qthelp

src/gui/rhi/qrhi.cpp

@@ -3529,6 +3529,7 @@ QRhi *QRhiResource::rhi() const
 
 /*!
     \class QRhiBuffer::NativeBuffer
+    \inmodule QtGui
     \brief Contains information about the underlying native resources of a buffer.
  */
 
@@ -3605,7 +3606,7 @@ QRhiResource::Type QRhiBuffer::resourceType() const
  */
 
 /*!
-    \fn void setUsage(UsageFlags u)
+    \fn void QRhiBuffer::setUsage(UsageFlags u)
     Sets the buffer's usage flags to \a u.
  */
 
@@ -3761,6 +3762,7 @@ void QRhiBuffer::endFullDynamicBufferUpdateForCurrentFrame()
 
 /*!
     \struct QRhiRenderBuffer::NativeRenderBuffer
+    \inmodule QtGui
     \brief Wraps a native renderbuffer object.
  */
 
@@ -4129,6 +4131,7 @@ bool QRhiRenderBuffer::createFrom(NativeRenderBuffer src)
 
 /*!
     \struct QRhiTexture::NativeTexture
+    \inmodule QtGui
     \brief Contains information about the underlying native resources of a texture.
  */
 
@@ -6088,16 +6091,6 @@ QDebug operator<<(QDebug dbg, const QRhiShaderResourceBindings &srb)
     \sa QRhiCommandBuffer, QRhi
  */
 
-/*!
-    \fn void QRhiGraphicsPipeline::setTargetBlends(const QList<TargetBlend> &blends)
-
-    Sets the blend specification for color attachments. Each element in \a
-    blends corresponds to a color attachment of the render target.
-
-    By default no blends are set, which is a shortcut to disabling blending and
-    enabling color write for all four channels.
- */
-
 /*!
     \enum QRhiGraphicsPipeline::Flag
 
@@ -6987,9 +6980,9 @@ QRhiResource::Type QRhiSwapChain::resourceType() const
   */
 
 /*!
-    \fn virtual bool QRhiSwapChain::isFormatSuported(Format f) = 0
+    \fn virtual bool QRhiSwapChain::isFormatSupported(Format f) = 0
 
-    \return true if the given swapchain format is supported. SDR is always
+    \return true if the given swapchain format \a f is supported. SDR is always
     supported.
 
     \note Can be called independently of createOrResize(), but window() must

src/gui/rhi/qshader.cpp

@@ -1009,6 +1009,7 @@ void QShader::removeResourceBindingMap(const QShaderKey &key)
 
 /*!
     \struct QShader::SeparateToCombinedImageSamplerMapping
+    \inmodule QtGui
     \brief Mapping metadata for sampler uniforms.
 
     Describes a mapping from a traditional combined image sampler uniform to
@@ -1083,6 +1084,7 @@ void QShader::removeSeparateToCombinedImageSamplerMappingList(const QShaderKey &
 
 /*!
     \struct QShader::NativeShaderInfo
+    \inmodule QtGui
     \brief Additional metadata about the native shader code.
 
     Describes information about the native shader code, if applicable. This