SCons: Silence MSVC C++17 deprecation warnings in Graphite

Fixes #66497.

modules/text_server_adv/SCsub

@@ -215,6 +215,9 @@ if env["builtin_graphite"] and freetype_enabled and env["graphite"]:
         ]
     )
 
+    if env.msvc:  # Not our business to fix.
+        env_graphite.Append(CCFLAGS=["-D_SILENCE_ALL_CXX17_DEPRECATION_WARNINGS"])
+
     lib = env_graphite.add_library("graphite_builtin", thirdparty_sources)
     thirdparty_obj += lib