Merge branch 'netlink-specs-add-ynl-spec-for-ovs_flow'

Donald Hunter says:

====================
netlink: specs: add ynl spec for ovs_flow

Add a ynl specification for ovs_flow. The spec is sufficient to dump ovs
flows but some attrs have been left as binary blobs because ynl doesn't
support C arrays in struct definitions yet.

Patches 1-3 add features for genetlink-legacy specs
Patch 4 is the ovs_flow netlink spec
====================

Link: https://lore.kernel.org/r/20230527133107.68161-1-donald.hunter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: kuba-moo

Documentation/netlink/genetlink-legacy.yaml

@@ -124,6 +124,12 @@ properties:
                 $ref: '#/$defs/len-or-define'
               byte-order:
                 enum: [ little-endian, big-endian ]
+              doc:
+                description: Documentation for the struct member attribute.
+                type: string
+              enum:
+                description: Name of the enum type used for the attribute.
+                type: string
         # End genetlink-legacy
 
   attribute-sets: