Update placement api-ref: allocations link in 1.11

Following on [1], this change updates the placement api-ref to include
the allocations link in the sample output for GET
/resource_providers[/uuid].

[1] https://review.openstack.org/499826

Depends-On: I6a1d320ce914926791d5f45e89bf4c601a6b10a0

Change-Id: I161da67258afaccd90df12364153f068ef55a3b1

placement-api-ref/source/get-resource_provider.json

@@ -20,6 +20,10 @@
         {
             "href": "/placement/resource_providers/3b4005be-d64b-456f-ba36-0ffd02718868/traits",
             "rel": "traits"
+        },
+        {
+            "href": "/placement/resource_providers/3b4005be-d64b-456f-ba36-0ffd02718868/allocations",
+            "rel": "allocations"
         }
     ],
     "name": "Ceph Storage Pool",

placement-api-ref/source/get-resource_providers.json

@@ -23,6 +23,10 @@
         {
           "href": "/resource_providers/99c09379-6e52-4ef8-9a95-b9ce6f68452e/traits",
           "rel": "traits"
+        },
+        {
+          "href": "/resource_providers/99c09379-6e52-4ef8-9a95-b9ce6f68452e/allocations",
+          "rel": "allocations"
         }
       ],
       "name": "vgr.localdomain"
@@ -50,6 +54,10 @@
         {
           "href": "/resource_providers/d0b381e9-8761-42de-8e6c-bba99a96d5f5/traits",
           "rel": "traits"
+        },
+        {
+          "href": "/resource_providers/d0b381e9-8761-42de-8e6c-bba99a96d5f5/allocations",
+          "rel": "allocations"
         }
       ],
       "name": "pony1"

placement-api-ref/source/parameters.yaml

@@ -230,6 +230,9 @@ resource_provider_links:
 
     .. note:: Trait relationship link is available starting from version 1.6.
 
+    .. note:: Allocations relationship link is available starting from version
+              1.11.
+
 resource_provider_name:
   type: string
   in: body