Use ID_C_typedef rather than ID_typedef

This is more consistent with other flags that do not affect the
semantics of the program.

Author: thk123

src/ansi-c/ansi_c_declaration.cpp

@@ -148,7 +148,7 @@ typet ansi_c_declarationt::full_type(
 
   // retain typedef for dump-c
   if(get_is_typedef())
-    result.set(ID_typedef,declarator.get_name());
+    result.set(ID_C_typedef,declarator.get_name());
 
   return result;
 }

src/ansi-c/c_typecheck_type.cpp

@@ -52,7 +52,7 @@ void c_typecheck_baset::typecheck_type(typet &type)
     c_qualifiers+=c_qualifierst(type.subtype());
     bool packed=type.get_bool(ID_C_packed);
     exprt alignment=static_cast<const exprt &>(type.find(ID_C_alignment));
-    irept _typedef=type.find(ID_typedef);
+    irept _typedef=type.find(ID_C_typedef);
 
     type.swap(type.subtype());
 
@@ -62,7 +62,7 @@ void c_typecheck_baset::typecheck_type(typet &type)
     if(alignment.is_not_nil())
       type.add(ID_C_alignment, alignment);
     if(_typedef.is_not_nil())
-      type.add(ID_typedef, _typedef);
+      type.add(ID_C_typedef, _typedef);
 
     return; // done
   }

src/ansi-c/expr2c.cpp

@@ -232,9 +232,9 @@ std::string expr2ct::convert_rec(
   std::string d=
     declarator==""?declarator:" "+declarator;
 
-  if(src.find(ID_typedef).is_not_nil())
+  if(src.find(ID_C_typedef).is_not_nil())
   {
-    return q+id2string(src.get(ID_typedef))+d;
+    return q+id2string(src.get(ID_C_typedef))+d;
   }
 
   if(src.id()==ID_bool)

src/util/irep_ids.txt

@@ -251,6 +251,7 @@ concatenation
 infinity
 return_type
 typedef
+C_typedef
 extern
 static
 auto