Move libartd-simulator dependency to host-only

libartd-simulator wasn't supposed to be building for the device,
but due to a bug in soong the device_supported: false in
libart_simluator_defaults wasn't taking effect.  Move the
dependency to the host section so that the soong bug can be fixed.

Test: m -j test-art-host-gtest-codegen_test64
Change-Id: I9becf348a9c9f26d7c14dbac5ca443e5aca47b00