1. Added package_get_auto_pr to PACKAGEFUNCS to get the auto
incremented value(PRAUTO) from remote PR service.
2. use PKGV/PKGR for pkgdata which will be used by package_write_xxx.
3. Added supporting functions in prserv.bbclass.
(From OE-Core rev: b1f6120c04731d3d66f322ce550b0d223c118dab)
Signed-off-by: Lianhao Lu <lianhao.lu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
