net/cnxk: support vector Tx multi-segment for CN20K

Add Tx multi-seg support for cn20k.

Signed-off-by: Nithin Dabilpuram <[email protected]>
Signed-off-by: Jerin Jacob <[email protected]>
Signed-off-by: Rahul Bhansali <[email protected]>
Signed-off-by: Pavan Nikhilesh <[email protected]>

Author: nithind1988