treewide: consolidate upgrade state set

Set the (sys)upgrade state when sourcing the stage2 script instead of
setting the state for each target individual.

This change fixes the, due to a missing state set, not working upgrade
led on ath79 and apm821xx.

Signed-off-by: Mathias Kresin <dev@kresin.me>

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

@@ -211,6 +211,11 @@ jffs2_copy_config() {
 	fi
 }
 
+indicate_upgrade() {
+	. /etc/diag.sh
+	set_state upgrade
+}
+
 # Flash firmware to MTD partition
 #
 # $(1): path to image