Adding more bluetooth stack fuzzers.

This change adds fuzzers for the following stack components:
* SMP
* GATT
* BNEP
* AVRC/AVCT
* L2CAP

Bug: 277109918
Bug: 276759518

Test: Manually build and test
Merged-In: Ie624b4cbc8ac960d908ab62663d5a5dd5d5a8b63
Change-Id: Ie624b4cbc8ac960d908ab62663d5a5dd5d5a8b63