Fixing update unified limit api-ref

In registered as well as project limit update api
param resource_name, service_id, default_limit and
resource_limit are optional but not mentioned in
api-ref. This patch updates the api-ref
for these parameter stating these as optional.
Also modifies description in reference with
the related patch.

Change-Id: I423f540a07aebf638ef93e22393ee49a228e7c49
Related-Patch: https://review.openstack.org/#/c/609985

api-ref/source/v3/parameters.yaml

@@ -1567,6 +1567,33 @@ request_application_credential_user_body_not_required:
   in: body
   required: false
   type: object
+request_default_limit_body_not_required:
+  description: |
+    The default limit for the registered limit.
+  in: body
+  required: false
+  type: integer
+request_resource_limit_body_not_required:
+  description: |
+    The override limit.
+  in: body
+  required: false
+  type: integer
+request_resource_name_body_not_required:
+  description: |
+    The resource name.Either service_id or resource_name must be
+    different than existing value otherwise it will raise 409.
+  in: body
+  required: false
+  type: string
+request_service_id_registered_limit_body_not_required:
+  description: |
+    The UUID of the service to update to which the registered
+    limit belongs. Either service_id or resource_name must be
+    different than existing value otherwise it will raise 409.
+  in: body
+  required: false
+  type: string
 resource_limit:
   description: |
     The override limit.

api-ref/source/v3/unified_limits.inc

@@ -162,10 +162,10 @@ Parameters
 
    - registered_limit_id: registered_limit_id_path
    - registered_limit: registered_limit
-   - service_id: service_id_registered_limit
+   - service_id: request_service_id_registered_limit_body_not_required
    - region_id: region_id_request_body
-   - resource_name: resource_name
-   - default_limit: default_limit
+   - resource_name: request_resource_name_body_not_required
+   - default_limit: request_default_limit_body_not_required
    - description: description_registered_limit_request_body
 
 Example
@@ -486,7 +486,7 @@ Update Limits
 
 .. rest_method::  PATCH /v3/limits/{limit_id}
 
-Updates the specifeid limit. It only supports to update ``resource_limit`` or
+Updates the specified limit. It only supports to update ``resource_limit`` or
 ``description`` for the limit.
 
 Relationship: ``https://docs.openstack.org/api/openstack-identity/3/rel/limit``
@@ -501,7 +501,7 @@ Parameters
 
    - limit_id: limit_id_path
    - limit: limit
-   - resource_limit: resource_limit
+   - resource_limit: request_resource_limit_body_not_required
    - description: description_limit_request_body
 
 Example