[LE Audio] Broadcast UI for Media output broadcast dialog

- Create the new dialog for broadcast that extands from
  MediaOutputBaseDialog and add the QR code view area.

- Create the edit dialog for the user to update broadcast name and
  broadcast code.

- Create the dialog for notifying the user that the broadcast feature is
  avaliable.

- We will add the test case for the Broadcast Dialog in next change
  list. This change list only for the UI part, and the Metadata will
  pass into the Broadcast Dialog in b/222674827.

- About the AndroidLint warning for contentDescription, we filed a bug
  b/226271667 for tracking the warning with the UX designer.

Bug: 214493779
Test: manual test
Change-Id: I37a6c0a3319560fb8f81ac45be3cb6465202dd13