netmgrd: allow netmgrd to acquire wakelock

Add policies to allow netmgrd to acquire and
release wakelocks.

Fix the following denials

avc: denied { read write } for comm="netmgrd" name="wake_lock"
dev="sysfs" ino=77 scontext=u:r:netmgrd:s0 tcontext=u:
object_r:sysfs_wake_lock:s0 tclass=file permissive=0

avc: denied { block_suspend } for pid=1073 comm="netmgrd"
capability=36 scontext=u:r:netmgrd:s0 tcontext==u:
r:netmgrd:s0 tclass=capability2 permissive=0

Change-Id: I305c30da5eca62ee7fbe224dc153fa4bbda2255e