atftp: move to meta-networking and tweak

* Add origin and Upstream-Status to patches
* Set SUMMARY instead of DESCRIPTION
* Add ${PN}d to PACKAGES instead of atftpd to be consistent with the
  rest of the recipe

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>