The Flavor Access __repr__ method was crashing because
it was using a non-existing attribute called "name".
On this fix, this method will now return the following:
<FlavorAccess flavor id: {flavor_id}, tenant id: {tenant_id}>
Closes-bug: #1331602
Change-Id: Ia2c24312e59e6c0aba1009766a15d390dc2721b1