kmod: upgrade to 20

kmod: upgrade to 20

The following patches are rebased.
-- Change-to-calling-bswap_-instead-of-htobe-and-be-toh.patch
-- avoid_parallel_tests.patch

The ptest part of kmod is removed because new version of kmod port all tests to
use modules from module-playground instead of copying prebuilt modules to the
repository. So, we cannot use ptest as before. Remove it so that kmod can build
successfully.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>