DolphinQt2: Fix MSBuild for Visual Studio.

Null VideoBackend is not being linked correctly.

Source/Core/DolphinQt2/DolphinQt2.vcxproj

@@ -189,6 +189,9 @@
     <ProjectReference Include="$(CoreDir)VideoBackends\Software\Software.vcxproj">
       <Project>{a4c423aa-f57c-46c7-a172-d1a777017d29}</Project>
     </ProjectReference>
+    <ProjectReference Include="$(CoreDir)VideoBackends\Null\Null.vcxproj">
+      <Project>{53A5391B-737E-49A8-BC8F-312ADA00736F}</Project>
+    </ProjectReference>
     <ProjectReference Include="$(CoreDir)VideoCommon\VideoCommon.vcxproj">
       <Project>{3de9ee35-3e91-4f27-a014-2866ad8c3fe3}</Project>
     </ProjectReference>

Source/Core/DolphinQt2/MainWindow.cpp

@@ -8,6 +8,7 @@
 #include <QMessageBox>
 
 #include "Core/BootManager.h"
+#include "Core/ConfigManager.h"
 #include "Core/Core.h"
 #include "Core/HW/ProcessorInterface.h"
 #include "Core/Movie.h"

Source/dolphin-emu.sln

@@ -1,6 +1,6 @@
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 14
-VisualStudioVersion = 14.0.25123.0
+VisualStudioVersion = 14.0.25420.1
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "Dolphin", "Core\DolphinWX\DolphinWX.vcxproj", "{47411FDB-1BF2-48D0-AB4E-C7C41160F898}"
 EndProject
@@ -73,6 +73,7 @@ EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "curl", "..\Externals\curl\curl.vcxproj", "{BB00605C-125F-4A21-B33B-7BF418322DCB}"
 EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "D3D12", "Core\VideoBackends\D3D12\D3D12.vcxproj", "{570215B7-E32F-4438-95AE-C8D955F9FCA3}"
+EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "DolphinQt2", "Core\DolphinQt2\DolphinQt2.vcxproj", "{FA3FA62B-6F58-4B86-9453-4D149940A066}"
 EndProject
 Global