[Media TTT] Define a common controller that will be used for both the

sender device chip and the receiver device chip.

Code for the receiver device chip will be added in future CLs.

Bug: 203800646
Test: manual (verify sender chip still works)
Test: MediaTttChipControllerSenderTest, MediaTttCommandLineHelperTest
Change-Id: I72c7e089c5b587fcdf5827f4e95f9032d96bbfd7