staging: bcm2835-audio: select BCM2835_VCHIQ rather then depending on it.

Change the audio's dependency on BCM2835_VCHIQ to a select
since audio support is typically more important to people
then base VCHIQ(which they may not even know what it's for).

Also, with a dependency the audio support would not be
visiable until VCHIQ is selected first, and that may
not be what most people would expect.

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