Use oslo_middleware sizelimit

In Kilo, cinder.api.middleware.sizelimit was replaced by a
compatabilityshim calling in to oslo_middleware.sizelimit and a
deprecation log message was added to indicate the change to
use oslo_middleware [1].  However, the wsgi api-paste.ini file
still uses cinder.api.middleware.sizelimit.

This commit modifies api-paste.ini to use oslo_middlware.sizelimit
directly, thereby allowing removal of the compatabilty shim in
the next release.

[1] Ia99ab479cb8ef63a0db1a1208cc2501abba6132c

Change-Id: Ic0e2c401b0facdd9abe954b0531d970abf4bca22

cinder/api/middleware/sizelimit.py

@@ -15,7 +15,9 @@
 Request Body limiting middleware.
 Compatibility shim for Kilo, while operators migrate to oslo.middleware.
 """
-
+# TODO(tbarron): remove this shim in Ocata.  Note that although the shim
+# was added in Kilo, api-paste.ini was not converted to use oslo.middleware
+# until Newton.
 
 from oslo_config import cfg
 from oslo_log import versionutils

etc/cinder/api-paste.ini

@@ -47,7 +47,7 @@ paste.filter_factory = osprofiler.web:WsgiMiddleware.factory
 paste.filter_factory = cinder.api.middleware.auth:NoAuthMiddleware.factory
 
 [filter:sizelimit]
-paste.filter_factory = cinder.api.middleware.sizelimit:RequestBodySizeLimiter.factory
+paste.filter_factory = oslo_middleware.sizelimit:RequestBodySizeLimiter.factory
 
 [app:apiv1]
 paste.app_factory = cinder.api.v1.router:APIRouter.factory

releasenotes/notes/use-oslo_middleware_sizelimit-5f171cf1c44444f8.yaml

@@ -0,0 +1,9 @@
+---
+upgrade:
+  - use oslo_middleware.sizelimit rather than cinder.api.middleware.sizelimit
+    compatibility shim
+deprecations:
+  - cinder.api.middleware.sizelimit was deprecated in kilo and compatability
+    shim added to call into oslo_middleware.  Using oslo_middleware.sizelimit
+    directly will allow us to remove the compatability shim in a future
+    release.