Remove XenAPI driver deprecation warning log message

This reverts commit 8404694. CI has
been running for XenAPI and all requirements have been met such that we
will not be removing XenAPI.

Change-Id: I544bb642fdd72aef28bcaf809c34d5db43ce0937

nova/virt/xenapi/driver.py

@@ -169,12 +169,6 @@ def host_state(self):
         return self._host_state
 
     def init_host(self, host):
-        LOG.warning(_('The xenapi driver does not meet the Nova project\'s '
-                      'requirements for quality verification and is planned '
-                      'for removal. This may change, but users should plan '
-                      'accordingly. Additional details here: '
-                      'https://wiki.openstack.org/wiki/HypervisorSupportMatrix'
-                      '/DeprecationPlan'))
         if CONF.xenserver.check_host:
             vm_utils.ensure_correct_host(self._session)