staging: bcm2835-audio: initial staging submission

Initial cleanup of bcm2835-audio driver for the
bcm2535(Raspberry PI)

Driver provides HDMI audio through ALSA and is built
on top of the vc04_services driver.

Original version of the driver is available at:
http://www.github.com/raspberry/linux



Driver compiles without any build errors or warnings.

Tested on a RPI 3 running in ARM64 mode with the
vlc player and alsautils.

Signed-off-by: Michael Zoran <mzoran@crowfest.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>