staging: bcm2835-audio: Enable compile test

Enable the compilation test for bcm2835-audio to gain more build coverage.
Signed-off-by: NStefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: NNicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vc04_services/bcm2835-audio/Kconfig

 config SND_BCM2835
         tristate "BCM2835 Audio"
-        depends on ARCH_BCM2835 && SND
+        depends on (ARCH_BCM2835 || COMPILE_TEST) && SND
         select SND_PCM
         select BCM2835_VCHIQ
         help