Allow mpdecision /proc read access

Allow mpdecision to read /proc entries associated with other UIDs.

Bug: 23310674
Change-Id: Ie5cf6d58068d27b70318bb9f83029b804bacb6b9
diff --git a/init.shamu.rc b/init.shamu.rc
index 63e7144..ce9a187 100644
--- a/init.shamu.rc
+++ b/init.shamu.rc
@@ -533,6 +533,7 @@
 service mpdecision /system/bin/mpdecision --avg_comp
    class main
    user root
+   group root readproc
 
 service ss_ramdump /system/bin/subsystem_ramdump
     class main