scripts: generate_manifest: remove obsolete manifest lines (#2067)

The current manifest format was introduced with the new autoupdater in
Gluon v2018.1. Reduce the manifest size by 70% by removing the additional
manifest lines added for backwards compatiblity.

scripts/generate_manifest.lua

@@ -20,11 +20,8 @@ local function generate_line(model, dir, filename, filesize)
 	end
 
 	local file256sum = strip(lib.exec_capture {'scripts/sha256sum.sh', dir..'/'..filename})
-	local file512sum = strip(lib.exec_capture {'scripts/sha512sum.sh', dir..'/'..filename})
 
 	io.stdout:write(string.format('%s %s %s %s %s\n', model, env.GLUON_RELEASE, file256sum, filesize, filename))
-	io.stdout:write(string.format('%s %s %s %s\n', model, env.GLUON_RELEASE, file256sum, filename))
-	io.stdout:write(string.format('%s %s %s %s\n', model, env.GLUON_RELEASE, file512sum, filename))
 end
 
 local function generate(image)

scripts/sha512sum.sh

-#!/bin/sh
-
-check_command() {
-	command -v "$1" >/dev/null 2>&1
-}
-
-if check_command sha512sum; then
-	ret="$(sha512sum "$@")"
-elif check_command shasum; then
-	ret="$(shasum -a 512 "$@")"
-elif check_command cksum; then
-	ret="$(cksum -q -a sha512 "$@")"
-else
-	echo "$0: no suitable sha512sum implementation was found" >&2
-	exit 1
-fi
-
-[ "$?" -eq 0 ] || exit 1
-
-echo "$ret" | awk '{ print $1 }'