api: make vpp api handlers endian independent

api: make vpp api handlers endian independent

Add a new boolean to signal that the API infrastructure should performan any required
endian conversions for the API handler.

  am->is_autoendian[mm->msg_id_base + VL_API_MAP_ADD_DOMAIN] = 1;

Similarly add new REPLY_ macros that perform endian conversion.

These changes do not change the on-the-wire encoding of the API messages, and therefore the API CRC is not changed.

Type: feature
Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: I7588f8ccb38b2d1e8d85ea17be99bac43f756267
Signed-off-by: Ole Troan <ot@cisco.com>