vsftpd: move from meta-oe to meta-networking and tweak

* Fix stripped file QA warning
* Add proper headers to patches (and split makefile.patch into two
  parts, one of which may be upstreamable)
* Use PV in SRC_URI instead of hardcoded version
* Move SRC_URI checksums up next to SRC_URI
* Set SUMMARY instead of DESCRIPTION

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