net: add CRC computation API

net: add CRC computation API

APIs for selecting the architecure specific implementation and computing
the crc (16-bit and 32-bit CRCs) are added. For CRCs calculation, scalar
as well as x86 intrinsic(sse4.2) versions are implemented.

The scalar version is based on generic Look-Up Table(LUT) algorithm,
while x86 intrinsic version uses carry-less multiplication for
fast CRC computation.

Signed-off-by: Jasvinder Singh <jasvinder.singh@intel.com>
Acked-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>