Policy updates to bring inline with AOSP.

* Move SEPOLICY vars to BoardConfigCommon.mk
  so tilapia can use.
* Bring over rild policy from AOSP. Though not
  explicitly used by grouper, tilapia needs it.
* Other small policy additions and subtractions.

Change-Id: I6da76b965d44866accb9e21496fe524f70d0cdd3
Signed-off-by: rpcraig <rpcraig@tycho.ncsc.mil>

Conflicts:
	BoardConfig.mk
	BoardConfigCommon.mk
	sepolicy/system.te