[dxgi] Use a recursive mutex.

Some games, like Final Fantasy XIV, call `SetFullscreenState()` again
after the window is resized. When the resize itself was triggered by a
`SetFullscreenState()` call, this will cause us to re-enter the mutex.

src/dxgi/dxgi_swapchain.cpp

@@ -256,7 +256,7 @@ namespace dxvk {
     if (PresentFlags & DXGI_PRESENT_TEST)
       return S_OK;
     
-    std::lock_guard<std::mutex> lockWin(m_lockWindow);
+    std::lock_guard<std::recursive_mutex> lockWin(m_lockWindow);
     std::lock_guard<std::mutex> lockBuf(m_lockBuffer);
 
     // Higher values are not allowed according to the Microsoft documentation:
@@ -320,7 +320,7 @@ namespace dxvk {
 
 
   HRESULT STDMETHODCALLTYPE DxgiSwapChain::ResizeTarget(const DXGI_MODE_DESC* pNewTargetParameters) {
-    std::lock_guard<std::mutex> lock(m_lockWindow);
+    std::lock_guard<std::recursive_mutex> lock(m_lockWindow);
 
     if (pNewTargetParameters == nullptr)
       return DXGI_ERROR_INVALID_CALL;
@@ -378,7 +378,7 @@ namespace dxvk {
   HRESULT STDMETHODCALLTYPE DxgiSwapChain::SetFullscreenState(
           BOOL          Fullscreen,
           IDXGIOutput*  pTarget) {
-    std::lock_guard<std::mutex> lock(m_lockWindow);
+    std::lock_guard<std::recursive_mutex> lock(m_lockWindow);
 
     if (m_descFs.Windowed && Fullscreen)
       return this->EnterFullscreenMode(pTarget);

src/dxgi/dxgi_swapchain.h

@@ -168,7 +168,7 @@ namespace dxvk {
       RECT rect    = { 0, 0, 0, 0 };
     };
     
-    std::mutex                      m_lockWindow;
+    std::recursive_mutex            m_lockWindow;
     std::mutex                      m_lockBuffer;
 
     Com<IDXGIFactory>               m_factory;