omni: sepolicy: Add posix-type fs rules for sdcards.

Everything below holds for sdcards formatted with a
ext4 / f2fs or alike filesystem.

* Allow filesystem context relabeling from vold that is
  required to set the correct context.
* Grant access to the sdcard for untrusted_app,
  untrusted_app_25, priv_app, and platform_app.
* Label files & dirs below a corresponding sdcard with
  sdcard_posix (set in genfscontext).
* Allow installd to get the quota.
* Allow sdcard access for the mediaprovider.

Change-Id: I7b0347010e7bc11a461b0120f75095d5d6ad0c70
Signed-off-by: Alexander Diewald <Diewi@diewald-net.com>
diff --git a/sepolicy/vold.te b/sepolicy/vold.te
index 9d05d8b..4ee8613 100644
--- a/sepolicy/vold.te
+++ b/sepolicy/vold.te
@@ -23,3 +23,6 @@
 
 allow vold fsck_exec:lnk_file { read };
 
+# Posix sdcard fs relabeling
+allow vold labeledfs:filesystem { relabelfrom relabelto };
+allow vold sdcard_posix:filesystem { relabelfrom relabelto };