Introduce a new parameter in driver_internal_info called
agent_erase_devices_zeroize to control the behavior of shred. This
parameter controls the --zero argument used when invoking shred.
Configuring this to false disabled the last pass of zeroes, leaving the
device with random data.
Change-Id: I7053034f5b5bc6737b535ee601e6fb71284d4a83
Partial-bug: #1568811
Depends-On: Ia7ea8d909df9ae86a6dbd68ba94746b171535eb8