Floss: LeRand BTIF + Topshim + Topshim test

This allows the application to generate a random number with the
controller.

This is being used by #floss in order to synchronize the suspend/resume
calls.

Bug: 219982747
Bug: 220182854
Test: system/gd/cert/run_topshim
Test: mma -j $(nproc)
Test: ./build.py
Tag: #floss
Change-Id: I59af5449ac3e8aa2eb8a4eb174829dba90b9d132