Floss: Add GATT interface to suspend module.

Bug: 233128294
Bug: 193686696
Bug: 193686094
Bug: 234029443
Test: mma -j $(nproc)
Test: ./build.py
Test: system/gd/cert/run --clean --topshim
Tag: #floss
Change-Id: I7dcab1defd150b4b9e461e162383548745c08579