releasetools: Fix undefined reference error
diff --git a/releasetools/releasetools.py b/releasetools/releasetools.py
index 7b82820..5973011 100755
--- a/releasetools/releasetools.py
+++ b/releasetools/releasetools.py
@@ -20,9 +20,8 @@
 
 def FullOTA_InstallEnd(info):
 
-    if ~ is_mounted("/system"):
-        info.script.Print("Mounting /system...")
-        mount("ext4", "MTD", "system", "/system")
+    info.script.Print("Mounting /system...")
+    info.script.AppendExtra('ifelse(is_mounted("/system"), ui_print("/system is mounted."), mount("ext4", "MTD", "system", "/system"));')
 
     info.script.Print("Detecting device variant ...")
     if is_substring("G530W", getprop("ro.bootloader")):