sepolicy: Add some permissions for nfc and wifi

Change-Id: I46fa7627ef6b7bc5d5634521996e5930e2c9cc4a
sepolicy: Allow zygote to read system properties

Change-Id: I34f0916978d74076a73f87e65a21492edda9a811
sepolicy: Vold needs to deal with external sdcards

Change-Id: I700bdc136fbbf438ad536151508e6d53dc91ac07