ofp-util: Abstract flow_mod OFPFF_* flags.
The OFPFF_* flags used in flow_mods are just confusing enough that it
seems worthwhile to try to abstract them out. In particular:
* OFPFF_EMERG was introduced in OF1.0, deleted in OF1.1, and then
its bit was reused for a different purpose in OF1.2.
* OFPFF_RESET_COUNTS was introduced in OF1.2 but the semantics that it
specifies are implied by "add" commands in earlier versions, so
proper translation requires the OpenFlow version number and flow_mod
command.
This commit does the abstraction.
Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>