This change removes the permissive line from unconfined
domains. Unconfined domains can do (mostly) anything, so moving
these domains into enforcing should be a no-op.

The following domains were deliberately NOT changed:
1) kernel
2) init

In the future, this gives us the ability to tighten up the
rules in unconfined, and have those tightened rules actually
work.

When we're ready to tighten up the rules for these domains,
we can:

1) Remove unconfined_domain and re-add the permissive line.
2) Submit the domain in permissive but NOT unconfined.
3) Remove the permissive line
4) Wait a few days and submit the no-permissive change.

For instance, if we were ready to do this for adb, we'd identify
a list of possible rules which allow adbd to work, re-add
the permissive line, and then upload those changes to AOSP.
After sufficient testing, we'd then move adb to enforcing.
We'd repeat this for each domain until everything is enforcing
and out of unconfined.

Change-Id: If674190de3262969322fb2e93d9a0e734f8b9245

This change does several things:

1) Restore domain.te to the version present at
cd516a32 . This is the version
currently being distributed in AOSP.

2) Add "allow domain properties_device:file r_file_perms;" to
domain.te, to allow all domains to read /dev/__properties__ .
This change was missing from AOSP.

3) Restore netd.te to the version present at
80c9ba52 . This is the version
currently being distributed in AOSP.

4) Remove anything involving module loading from netd.te. CTS
enforces that Android kernels can't have module loading enabled.

5) Add several new capabilities, plus data file rules, to
netd.te, since netd needs to write to files owned by wifi.

6) Add a new unconfined domain called dnsmasq.te, and allow
transitions from netd to that domain. Over time, we'll tighten up
the dnsmasq.te domain.

7) Add a new unconfined domain called hostapd.te, and allow
transitions from netd to that domain. Over time, we'll tighten up
the hostapd.te domain.

The net effect of these changes is to re-enable SELinux protections
for netd. The policy is FAR from perfect, and allows a lot of wiggle
room, but we can improve it over time.

Testing: as much as possible, I've exercised networking related
functionality, including turning on and off wifi, entering airplane
mode, and enabling tethering and portable wifi hotspots. It's quite
possible I've missed something, and if we experience problems, I
can roll back this change.

Bug: 9618347
Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0