fix umount error during upgrade mode

SD_ROOT/wz_mini/usr/bin/upgrade-run.sh

@@ -37,10 +37,13 @@ else
   exit 1
 fi
 
+echo "Backup user config"
 cp /opt/wz_mini/wz_mini.conf /opt/Upgrade/preserve/
 cp -r /opt/wz_mini/etc/ssh /opt/Upgrade/preserve/
 cp -r /opt/wz_mini/etc/wireguard /opt/Upgrade/preserve/
 sync
+
+echo "Rebooting into UPGRADE MODE"
 reboot
 }
 
@@ -85,9 +88,10 @@ if [[ "$V2" == "true" ]]; then
 
 echo UPGRADE MODE
 
-umount /opt/wz_mini/tmp
+umount -l /opt/wz_mini/tmp
 ls -l /opt/wz_mini/
 rm -rf /opt/wz_mini/*
+sync
 mv /opt/Upgrade/wz_mini_hacks-master/SD_ROOT/wz_mini/* /opt/wz_mini/
 rm -f /opt/factory_t31_ZMC6tiIDQN
 mv /opt/Upgrade/wz_mini_hacks-master/SD_ROOT/factory_t31_ZMC6tiIDQN /opt/factory_t31_ZMC6tiIDQN

file.chk

@@ -67,7 +67,7 @@ eaf86f91cb1b15b2191a8845ae88e3c8  SD_ROOT/wz_mini/usr/share/audio/init_v2.wav
 df71296985782eb0c111a95f36aa4648  SD_ROOT/wz_mini/usr/bin/watch_up.sh
 b339aee882a5d1c943ad08e4282ec3fd  SD_ROOT/wz_mini/usr/bin/iCamera-dbg
 20b061689308b2cee7edf3b9b906bca7  SD_ROOT/wz_mini/usr/bin/ucamera
-361443f420cbfc6402fef9d0b2510d36  SD_ROOT/wz_mini/usr/bin/upgrade-run.sh
+3857df7b578af3669022f2f2248b1bff  SD_ROOT/wz_mini/usr/bin/upgrade-run.sh
 47f88eecbd49de573335028dc72dab3e  SD_ROOT/wz_mini/usr/bin/rtmp-stream.sh
 4c780f0455481d106d47d89f0ae04ed5  SD_ROOT/wz_mini/lib/uClibc.tar
 9afeb088e4cbabbe0b04033b560204d0  SD_ROOT/wz_mini/lib/libimp.so