Silence C++ language server diagnostics in the example.

Author: whitequark

example/.vscode/c_cpp_properties.json

@@ -0,0 +1,14 @@
+{
+    "configurations": [
+        {
+            "name": "Linux",
+            "includePath": [
+                "${workspaceFolder}/**",
+                "${workspaceFolder}/../../yosys/backends/cxxrtl/runtime/"
+            ],
+            "defines": [],
+            "intelliSenseMode": "linux-clang-x64"
+        }
+    ],
+    "version": 4
+}