[util,d3d11] Be more robust against use-after-free

Sims 4 binds an SRV after destroying it, so we need to ensure our internal
view pointers are null or we'll create a problem otherwise.

src/d3d11/d3d11_view_dsv.cpp

@@ -106,6 +106,7 @@ namespace dxvk {
   
   D3D11DepthStencilView::~D3D11DepthStencilView() {
     ResourceReleasePrivate(m_resource);
+    m_resource = nullptr;
   }
   
   

src/d3d11/d3d11_view_rtv.cpp

@@ -116,6 +116,7 @@ namespace dxvk {
   
   D3D11RenderTargetView::~D3D11RenderTargetView() {
     ResourceReleasePrivate(m_resource);
+    m_resource = nullptr;
   }
   
   

src/d3d11/d3d11_view_srv.cpp

@@ -183,6 +183,7 @@ namespace dxvk {
   
   D3D11ShaderResourceView::~D3D11ShaderResourceView() {
     ResourceReleasePrivate(m_resource);
+    m_resource = nullptr;
   }
   
   

src/d3d11/d3d11_view_uav.cpp

@@ -129,6 +129,7 @@ namespace dxvk {
   
   D3D11UnorderedAccessView::~D3D11UnorderedAccessView() {
     ResourceReleasePrivate(m_resource);
+    m_resource = nullptr;
   }
   
   

src/util/com/com_pointer.h

@@ -96,6 +96,7 @@ namespace dxvk {
     
     ~Com() {
       this->decRef();
+      m_ptr = nullptr;
     }
     
     T* operator -> () const {

src/util/rc/util_rc_ptr.h

@@ -86,6 +86,7 @@ namespace dxvk {
     
     ~Rc() {
       this->decRef();
+      m_object = nullptr;
     }
     
     T& operator *  () const { return *m_object; }