Cleanup the Makefiles.
* Makefile.am (EXTRA_DIST): Remove removed patch.
(download): Remove packages.{3.4}.
* packages/Makefile.am (EXTRA_DIST): Ditto. Remove
get-gpg-package.sh. Add gen-gnupg.sh.
* packages/get-gpg-package.sh: Remove.
* packages/distsigkey.gpg: Update from gnupg master.Note that get-gpg-package.sh has been been replaced some time ago by
gen-gnupg.sh but that was not included in the distributed tarballs.