dpdk: allow configure individual VMBUS devices

dpdk: allow configure individual VMBUS devices

now startup.conf supports confuguration for VMBUS
devices as for PCI devices for whitelisting/blacklisting

dpdk { dev fa5a6e7a-cf3a-4b98-9569-addb479b84bc }
 with sub-configuration as for PCI devices
dpdk { blacklist fa5a6e7a-cf3a-4b98-9569-addb479b84bc }
 where fa5a6e7a-cf3a-4b98-9569-addb479b84bc - example of UUID

struct vlib_vmbus_addr_t changed to union with UUID described
 fields

Added device_config_index_by_vmbus_addr
      blacklist_by_vmbus_addr
to enumerate available device configs

hash_key is as_u32[0] field(last 4 bytes of UUID)
Lost of precision against full UUID, but 2^32 is enough
to handle all the devices available

Added is_blacklisted check while creating vnet devices in
order to supress creation of dev if it's blacklisted

Type: feature

Signed-off-by: Vladimir Ratnikov <vratnikov@netgate.com>
Change-Id: Id82611e54fed082190e488c7e5fbe14ecbe5b2ab