qapi-types: Don't filter out expressions with 'gen'

Useless, because it can only occur in commands, and we're not dealing
with commands here.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

scripts/qapi-types.py

@@ -329,7 +329,6 @@ fdecl.write(mcgen('''
 '''))
 
 exprs = parse_schema(input_file)
-exprs = filter(lambda expr: not expr.has_key('gen'), exprs)
 
 fdecl.write(guardstart("QAPI_TYPES_BUILTIN_STRUCT_DECL"))
 for typename in builtin_types.keys():