Floss: wrap HFP LC3 codec libraries with codec server

In this patch, HFP LC3 codec libraries are placed into |HfpLc3Encoder|
and |HfpLc3Decoder|, which inherit |MmcInterface|. Only |init|,
|cleanup|, and |transcode| are exposed to user to hide details.

Bug: 294165109
Tag: #floss
Test: m - None
Change-Id: I8790b90d472d260e3ac3bdf651c222572aa91583