dumpstate is a client of graphics allocator

This fixes

avc: denied { call } for comm="screencap" scontext=u:r:dumpstate:s0
  tcontext=u:r:hal_graphics_allocator_default:s0 tclass=binder
  permissive=0

Bug: 37360953
Test: adb shell dumpstate -p -o <path>
Change-Id: Ia9387559e3ec1ba51b614bb9d24294fbbbd51b1a