i40e: change ppp name to ddp

PPP name was going to be confusing since PPP already means point
to point protocol. It is decided to change pipeline personalization
profile(ppp) to dynamic device personalization(ddp).

Signed-off-by: Jingjing Wu <jingjing.wu@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>