VideoConfig: Remove fullscreen flags.

These weren't actually settings, they were used as a bad way to communicate with the GPU thread.

Source/Core/Core/Analytics.cpp

@@ -211,8 +211,6 @@ void DolphinAnalytics::MakePerGameBuilder()
   builder.AddData("cfg-gfx-realxfb", g_Config.RealXFBEnabled());
   builder.AddData("cfg-gfx-virtualxfb", g_Config.VirtualXFBEnabled());
   builder.AddData("cfg-gfx-vsync", g_Config.bVSync);
-  builder.AddData("cfg-gfx-fullscreen", g_Config.bFullscreen);
-  builder.AddData("cfg-gfx-exclusive-mode", g_Config.bExclusiveMode);
   builder.AddData("cfg-gfx-aspect-ratio", g_Config.iAspectRatio);
   builder.AddData("cfg-gfx-efb-access", g_Config.bEFBAccessEnable);
   builder.AddData("cfg-gfx-efb-scale", g_Config.iEFBScale);

Source/Core/VideoBackends/D3D/D3DBase.cpp

@@ -315,7 +315,7 @@ HRESULT Create(HWND wnd)
   swap_chain_desc.OutputWindow = wnd;
   swap_chain_desc.SampleDesc.Count = 1;
   swap_chain_desc.SampleDesc.Quality = 0;
-  swap_chain_desc.Windowed = !g_Config.bFullscreen;
+  swap_chain_desc.Windowed = TRUE;
 
   DXGI_OUTPUT_DESC out_desc = {};
   output->GetDesc(&out_desc);

Source/Core/VideoBackends/D3D12/Render.cpp

@@ -803,8 +803,6 @@ void Renderer::SwapImpl(u32 xfb_addr, u32 fb_width, u32 fb_stride, u32 fb_height
   SetWindowSize(fb_stride, fb_height);
 
   const bool window_resized = CheckForResize();
-  const bool fullscreen = g_ActiveConfig.bFullscreen && !g_ActiveConfig.bBorderlessFullscreen &&
-                          !SConfig::GetInstance().bRenderToMain;
 
   bool xfb_changed = s_last_xfb_mode != g_ActiveConfig.bUseRealXFB;
 

Source/Core/VideoCommon/VideoConfig.cpp

@@ -31,10 +31,6 @@ VideoConfig::VideoConfig()
 {
   bRunning = false;
 
-  // Exclusive fullscreen flags
-  bFullscreen = false;
-  bExclusiveMode = false;
-
   // Needed for the first frame, I think
   fAspectRatioHackW = 1;
   fAspectRatioHackH = 1;

Source/Core/VideoCommon/VideoConfig.h

@@ -63,8 +63,6 @@ struct VideoConfig final
 
   // General
   bool bVSync;
-  bool bFullscreen;
-  bool bExclusiveMode;
   bool bRunning;
   bool bWidescreenHack;
   int iAspectRatio;