init.qcom.post_boot: Enable mem_latency governor for msm8996

Enable memory latency governor for msm8996 for helping memory
latency intensive usecases. Remove the cpufreq governor setting
for mincpubw device since memory latency governor along with
bw_hwmon governor is sufficient for voting for higher DDR
frequencies for most memory bound workloads.
Set the polling_interval for mem_latency governor to 10ms.

Change-Id: I5715aea50452c02d57fe94538627fe00567106fe

rootdir/etc/init.qcom.post_boot.sh

@@ -1556,9 +1556,10 @@ case "$target" in
             echo 1600 > $cpubw/bw_hwmon/idle_mbps
         done
 
-        for devfreq_gov in /sys/class/devfreq/*qcom,mincpubw*/governor
+        for memlat in /sys/class/devfreq/*qcom,memlat-cpu*
         do
-            echo "cpufreq" > $devfreq_gov
+            echo "mem_latency" > $memlat/governor
+            echo 10 > $memlat/polling_interval
         done
 
 	soc_revision=`cat /sys/devices/soc0/revision`