Allow keystore to talk to the tee

On manta, the keystore CTS tests are failing, because
keystore isn't allowed to talk to the tee. Allow it.

I've only seen this bug on manta, but it seems appropriate
for all domains.

Fixes the following denial:

<5>[  286.249563] type=1400 audit(1389210059.924:6): avc:  denied  { connectto } for  pid=126 comm="keystore" path=006D636461656D6F6E scontext=u:r:keystore:s0 tcontext=u:r:tee:s0 tclass=unix_stream_socket

Bug: 12450710
Change-Id: I07133d9abeaf967392118ba478a5a391cf0c5fa5