iot bootaction: use libandroidthings types.

We now provide some parameters that can be set on reboot and passed into
the bootaction library. This becomes part of the public libandroidthings
native API, so we need to use the public type.

Bug: 65462981
Test: `mma` builds successfully
Test: Test bootaction.so can receive boot params (tested on nyc-iot-dev)
Change-Id: Ibf6548730e0bac023f6a0a3aef925b0938418a10