Switch to oslo_log

Change-Id: Id9ce71a53f4392ea1bd408681d01b6174d86ae61
diff --git a/requirements.txt b/requirements.txt
index 29091ac..b22bec8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,3 +4,4 @@
 
 pbr>=1.8 # Apache-2.0
 urllib3>=1.15.1 # MIT
+oslo.log>=3.11.0 # Apache-2.0