Add support for gnu3 demangler 'co-await'

Author: plafosse

demangler/gnu3/demangle_gnu3.cpp

@@ -102,6 +102,7 @@ static string GetOperator(char elm1, char elm2)
 	case hash('s','z'): return "sizeof";
 	case hash('a','t'): return "alignof";
 	case hash('a','z'): return "alignof";
+	case hash('a','w'): return "co_await";
 	case hash('n','x'): return "noexcept";
 	case hash('s','Z'): return "sizeof...";
 	case hash('s','P'): return "sizeof...";
@@ -1310,6 +1311,7 @@ DemangledTypeNode DemangleGNU3::DemangleUnqualifiedName()
 	case hash('s','z'):
 	case hash('a','t'):
 	case hash('a','z'):
+	case hash('a','w'):
 	case hash('n','x'):
 	case hash('s','Z'):
 	case hash('s','P'):