lib: crc: add CRC-32K/4.2

This adds the best HD=4 CRC32 polynomial. The discovery
is the result of research by Philip Koopman of Carnegie
Mellon University, and is well documented at
https://users.ece.cmu.edu/~koopman/crc/

.

The user is given the option of trading 1024B of RAM to
improve the execution speed. The unit tests are parameterized
with this KConfig option.

Signed-off-by: JP Hutchins <jp@intercreate.io>