Remove H307 no db in virt

This is a Nova only rule that shouldn't be in the generic hacking tool

Change-Id: Ibdba7319a1bf08fb917aaac8503203a857f08b83
Reviewed-on: https://review.openstack.org/27090
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Approved: Doug Hellmann <doug.hellmann@dreamhost.com>
Reviewed-by: Doug Hellmann <doug.hellmann@dreamhost.com>
Tested-by: Jenkins

README.rst

@@ -59,7 +59,6 @@ Imports
 - Do not import more than one module per line (*)
 - Do not use wildcard ``*`` import (*)
 - Do not make relative imports
-- Do not make new nova.db imports in nova/virt/*
 - Order your imports by the full module path
 - Organize your imports according to the following template
 

hacking/core.py

@@ -274,20 +274,6 @@ def hacking_import_alphabetical(logical_line, blank_lines, previous_logical,
                        % (split_previous[1], split_line[1]))
 
 
-@flake8ext
-def hacking_import_no_db_in_virt(logical_line, filename):
-    """Check for db calls from nova/virt
-
-    As of grizzly-2 all the database calls have been removed from
-    nova/virt, and we want to keep it that way.
-
-    H307
-    """
-    if "nova/virt" in filename and not filename.endswith("fake.py"):
-        if logical_line.startswith("from nova import db"):
-            yield (0, "H307: nova.db import not allowed in nova/virt/*")
-
-
 def is_docstring(physical_line, previous_logical):
     """Return True if found docstring
     'A docstring is a string literal that occurs as the first statement in a

setup.cfg

@@ -31,7 +31,6 @@ flake8.extension =
 	H202 = hacking.core:hacking_except_format_assert
 	H301 = hacking.core:hacking_import_rules
 	H306 = hacking.core:hacking_import_alphabetical
-	H307 = hacking.core:hacking_import_no_db_in_virt
 	H401 = hacking.core:hacking_docstring_start_space
 	H402 = hacking.core:hacking_docstring_one_line
 	H403 = hacking.core:hacking_docstring_multiline_end