Remove old TODO about forced_host policy check

The TODO added in Kilo [1] is removed here since
we have consolidated the server create extension
code into the main servers controller [2] which
makes the TODO irrelevant.

[1] If3c68af8a438e77045b2b719873fc39e8473b6ea
[2] I4d817e5516c8bea8f3bffb28683a1e041303dae9

Change-Id: Ibf08a9a9653bdc48ab1099a26fc9f9a9f70a33e2

Author: mriedem

nova/api/openstack/compute/servers.py

@@ -642,8 +642,6 @@ def create(self, req, body):
             context.can(server_policies.SERVERS % 'create:trusted_certs',
                         target=target)
 
-        # TODO(Shao He, Feng) move this policy check to os-availability-zone
-        # extension after refactor it.
         parse_az = self.compute_api.parse_availability_zone
         try:
             availability_zone, host, node = parse_az(context,