x86_64: fix invoking sysupgrade on PARTUUID mounted system

Fix sysupgrade to determine the correct boot block device to use if
/proc/cmdline contains a PARTUUID root.

Change the preinit move_config() hook to use the UUID scanning code
from sysupgrade in order to avoid code duplication.

Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>

SVN-Revision: 42968

target/linux/x86_64/base-files/lib/preinit/79_move_config

@@ -2,40 +2,10 @@
 # Copyright (C) 2012-2014 OpenWrt.org
 
 move_config() {
-	local cmdline uuid disk dev
+	. /lib/upgrade/platform.sh
 
-	if read cmdline < /proc/cmdline; then
-		case "$cmdline" in
-			*block2mtd=*)
-				disk="${cmdline##*block2mtd=}"
-				disk="${disk%%,*}"
-			;;
-			*root=*)
-				disk="${cmdline##*root=}"
-				disk="${disk%% *}"
-			;;
-		esac
-
-		case "$disk" in
-			PARTUUID=[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-02)
-				uuid="${cmdline#PARTUUID=}"
-				uuid="${uuid%-02}"
-				for disk in /dev/[hsv]d[a-z]; do
-					set -- $(dd if=$disk bs=1 skip=440 count=4 2>/dev/null | hexdump -v -e '4/1 "%02x "')
-					if [ "$4$3$2$1" = "$uuid" ]; then
-						dev="${disk}1"
-						break
-					fi
-				done
-			;;
-			/dev/*)
-				dev="${disk%[0-9]}1"
-			;;
-		esac
-	fi
-
-	if [ -n "$dev" ]; then
-		mount -t ext4 -o rw,noatime "$dev" /mnt
+	if platform_export_bootpart; then
+		mount -t ext4 -o rw,noatime "$BOOTPART" /mnt
 		mv -f /mnt/sysupgrade.tgz /
 		umount /mnt
 	fi