odp-util: Make sure vlan tci mask has exact match for VLAN_CFI.

odp-util: Make sure vlan tci mask has exact match for VLAN_CFI.

OVS datapath has check which prevents the installation of flow
that matches VLAN TCI but does not have exact match for VLAN_CFI
bit.  To follow this rule, ovs userspace must make sure the
flow key for datapath flow matching VLAN TCI has exact match for
VLAN_CFI bit.

Before this commit, this is not enforced, so OpenFlow flow like
"vlan_tci=0x000a/0x0fff,action=output:local" can generate datapath
flow like "vlan(vid=10/0xfff,pcp=0/0x0,cfi=1/0)".

With the OVS datapath check, the installation of such datapath
flow will be rejected with:
"|WARN|system@ovs-system: failed to put[create][modify] (Invalid argument)"

This commit makes ovs userspace always exact match the VLAN_CFI
bit if the flow matches VLAN TCI.

Reported-by: Ronald Lee <ronaldlee@vmware.com>
Signed-off-by: Alex Wang <alexw@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>