base-files: drop support for NAND upgrade in platform_pre_upgrade()

With bcm53xx switched to the new procedure there is no more need for
keeping that backward compatibility code.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
(cherry picked from commit ea4e1dac71dfa015c0da10e68149478fa25878f9)

package/base-files/Makefile

@@ -12,7 +12,7 @@ include $(INCLUDE_DIR)/version.mk
 include $(INCLUDE_DIR)/feeds.mk
 
 PKG_NAME:=base-files
-PKG_RELEASE:=202
+PKG_RELEASE:=203
 PKG_FLAGS:=nonshared
 
 PKG_FILE_DEPENDS:=$(PLATFORM_DIR)/ $(GENERIC_PLATFORM_DIR)/base-files/

package/base-files/files/lib/upgrade/common.sh

@@ -228,9 +228,7 @@ default_do_upgrade() {
 
 do_upgrade_stage2() {
 	v "Performing system upgrade..."
-	if [ -n "$do_upgrade" ]; then
-		eval "$do_upgrade"
-	elif type 'platform_do_upgrade' >/dev/null 2>/dev/null; then
+	if type 'platform_do_upgrade' >/dev/null 2>/dev/null; then
 		platform_do_upgrade "$IMAGE"
 	else
 		default_do_upgrade "$IMAGE"

package/base-files/files/lib/upgrade/nand.sh

@@ -280,15 +280,6 @@ nand_upgrade_tar() {
 
 # Recognize type of passed file and start the upgrade process
 nand_do_upgrade() {
-	if [ -n "$IS_PRE_UPGRADE" ]; then
-		# Previously, nand_do_upgrade was called from the platform_pre_upgrade
-		# hook; this piece of code handles scripts that haven't been
-		# updated. All scripts should gradually move to call nand_do_upgrade
-		# from platform_do_upgrade instead.
-		export do_upgrade="nand_do_upgrade '$1'"
-		return
-	fi
-
 	local file_type=$(identify $1)
 
 	if type 'platform_nand_pre_upgrade' >/dev/null 2>/dev/null; then

package/base-files/files/lib/upgrade/stage2

@@ -136,10 +136,7 @@ sleep 1
 
 
 if [ -n "$IMAGE" ] && type 'platform_pre_upgrade' >/dev/null 2>/dev/null; then
-	IS_PRE_UPGRADE=1 platform_pre_upgrade "$IMAGE"
-
-	# Needs to be unset again because of busybox weirdness ...
-	IS_PRE_UPGRADE=
+	platform_pre_upgrade "$IMAGE"
 fi
 
 if [ -n "$(rootfs_type)" ]; then