codegen: Use has_end_attr instead of has_attr("end")

Just style, they do the same thing, but is more coherent
with the rest of the code.

Signed-off-by: Frediano Ziglio <fziglio@redhat.com>
Acked-by: Uri Lublin <uril@redhat.com>

python_modules/demarshal.py

@@ -804,7 +804,7 @@ def write_array_parser(writer, member, nelements, array, dest, scope):
     element_type = array.element_type
     if member:
         array_start = dest.get_ref(member.name)
-        at_end = member.has_attr("end")
+        at_end = member.has_end_attr()
     else:
         array_start = "end"
         at_end = True