Allow perfd write access to sched_upmigrate and sched_downmigrate

avc: denied { write } for name="sched_upmigrate" dev="proc" ino=38724 scontext=u:r:perfd:s0 tcontext=u:object_r:proc_kernel_sched:s0 tclass=file permissive=0
avc: denied { write } for name="sched_downmigrate" dev="proc" ino=40730 scontext=u:r:perfd:s0 tcontext=u:object_r:proc_kernel_sched:s0 tclass=file permissive=0

Bug: 23331135
Change-Id: I5c77579c166a2121835223b85a23024139bec35e
diff --git a/sepolicy/perfd.te b/sepolicy/perfd.te
index 122f046..239f5a4 100644
--- a/sepolicy/perfd.te
+++ b/sepolicy/perfd.te
@@ -24,7 +24,7 @@
 allow perfd sysfs_thermal:dir search;
 allow perfd sysfs_thermal:file rw_file_perms;
 
-allow perfd proc_kernel_sched:file r_file_perms;
+allow perfd proc_kernel_sched:file rw_file_perms;
 
 # allow writing to /sys/devices/system/cpu/*
 allow perfd sysfs_devices_system_cpu:file rw_file_perms;