driver: net: ldpaa: Add debug info of printing DPMAC stats

Add debug information prints to provide DPMAC statistics
 - Number of bytes received
 - Number of received and discard frames
 - Number of bytes transferred
 - Number of frames transferred
 etc.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Reviewed-by: York Sun <york.sun@nxp.com>