staging: bcm2835-audio: fix style problem in vc_vchi_audioserv_defs.h

Remove spaces around parenthesized expression to conform to the
kernel coding style. Issue found by checkpatch.pl script.

Signed-off-by: Miquel Raynal <raynal.miquel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>