DataSourceOVF do not provide a default static hostname

This is the same change made in DataSourceNoCloud, but to the
OVF DataSource.

ChangeLog

@@ -48,6 +48,10 @@
    rather than appending.  This ensures that the authorized_keys that are being
    inserted actually do something (LP: #434076, LP: #833499)
  - log warning on failure to set hostname (LP: #832175)
+ - upstart/cloud-init-nonet.conf: wait for all network interfaces to be up
+ - DataSourceNoCloud, DataSourceOVF : do not provide a default hostname.
+   This way the configured hostname of the system will be used if not provided
+   by metadata (LP: #838280)
 
 0.6.1:
  - fix bug in fixing permission on /var/log/cloud-init.log (LP: #704509)

cloudinit/DataSourceOVF.py

@@ -51,7 +51,6 @@ class DataSourceOVF(DataSource.DataSource):
         ud = ""
 
         defaults = { 
-            "local-hostname" : "ubuntuhost",
             "instance-id" : "nocloud"
         }
 
@@ -109,9 +108,6 @@ class DataSourceOVF(DataSource.DataSource):
         if not 'public-keys' in self.metadata: return([])
         return([self.metadata['public-keys'],])
         
-    def get_hostname(self):
-        return(self.metadata['local-hostname'])
-
     # the data sources' config_obj is a cloud-config formated
     # object that came to it from ways other than cloud-config
     # because cloud-config content would be handled elsewhere