floss: Implement the PLC(Packet Loss Concealment)

The PLC is recommended to implement for HFP WBS based on Bluetooth
organization's HFP spec.

The PLC algorithm is based on HFP spec 1.7.1 and has been used by
Chrome OS since 2019/07. This CL follows the existing implementation
with limited modification to adjust the code flow and architecture of
btm_sco_hci.

Bug: 232463744
Tag: #floss
Test: atest --host net_test_stack_btm --no-bazel-mode &&
Build and verify HFP WBS PLC works under different signal
strength. Print log to verify each state of the PLC works.

BYPASS_LONG_LINES_REASON: Bluetooth likes 120 char lines

Change-Id: I5d02df4df75509ff076ec02f022b37698d121420