sepolicy: basic: non_plat: Allow mediacodec to read some props

W [email protected]: type=1400 audit(0.0:117): avc: denied { open } for path="/dev/__properties__/u:object_r:default_prop:s0" dev="tmpfs" ino=12368 scontext=u:r:mediacodec:s0 tcontext=u:object_r:default_prop:s0 tclass=file permissive=0
W libc    : Access denied finding property "ro.mtk_deinterlace_support"
W libc    : Access denied finding property "ro.mtk_crossmount_support"
W libc    : Access denied finding property "mtk.vendor.omx.core.log"

Change-Id: I14cbe8a4e6a7892b0b34d05c86b68281291d6579