AudioFormat: Support 13ch audio layout for 360 Reality Audio

 - Add definitions for the front bottom channels. The name
   of the definitions are standardized in ITU-R BS.2051-1.
 - Add definition for 13ch mask which consists of surround 5
   channels, top 5 channels and bottom 3ch channels. This
   channel mask is ideal speaker layout used by Sony 360
   Reality Audio. Virtualizer can place individual sounds in
   a 360 spherical sound field from these channels on any
   headphones.

Ignoring checkstyle warning, "'|' should be on a new line",
to keep existing codestyle.

Bug: 185100731
Test: atest AudioFormatTest
Test: Play wav with 13ch mask after OUT_CHANNEL_COUNT_MAX to 24
Change-Id: I2b4deaac740a08ae3b1b8d8453650a876e2d6206