[util] Set deviceLossOnFocusLoss for Assassin's Creed 2

Makes it not crash on alt tab using at least Proton. 
Windows will still have issues with alt tab.

src/util/config/config.cpp

@@ -836,6 +836,11 @@ namespace dxvk {
     { R"(\\SkyDrift\.exe$)" , {{
       { "d3d9.allowDirectBufferMapping",    "False" },
     }} },
+     /* Assassin's Creed 2                      *
+     *  Helps alt tab crash on Linux            */
+    { R"(\\AssassinsCreedIIGame\.exe$)" , {{
+      { "d3d9.deviceLossOnFocusLoss",       "True" },
+    }} },
 
     /**********************************************/
     /* D3D12 GAMES (vkd3d-proton with dxvk dxgi)  */