sm8450-common: rootdir: ss_ramdump: set io priority to realtime

Change-Id: Ie6af973c15cae9ae983041298caa130df9e5f0b1

rootdir/etc/init.qcom.rc

@@ -401,6 +401,7 @@ service vendor.ss_ramdump /system/vendor/bin/subsystem_ramdump
     class main
     user system
     group system
+    ioprio rt 4
     disabled
 
 on property:ro.vendor.iocgrp.config=1