Updated openstack/openstack
Project: openstack/nova  b2ce11bab0adf6d2804f497a5f11e796f72920d3

Correct exception info format of v3 flavor manage

The existing flavor manage may raise HTTPBadRequest exception,
But the msg info didn't use '_' prefix. This patch adds it.

Change-Id: I736bf4b0e78ecc0bb753d376ee162f19fafc09e1