ParserGen: fix compilation warning

Fix the following warning:

ParserGen.cs(208,26): warning CS0618: `CppSharp.AST.Declaration.Ignore' is obsolete: `Replace set by ExplicitlyIgnore(). Replace get by GenerationKind == GenerationKind.None.'

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@iki.fi>

src/CppParser/Bindings/ParserGen.cs

@@ -156,7 +156,7 @@ namespace CppSharp
 
         public override bool VisitFunctionDecl(Function function)
         {
-            if (function.Ignore)
+            if (function.GenerationKind == GenerationKind.None)
                 return false;
 
             if (function.Parameters.Any(param => IsStdType(param.QualifiedType)))