staging: vchiq_arm: clarify multiplication expressions

Add spaces around '*' in multiplication expressions to enhance
readability.

Reported by checkpatch.pl

Signed-off-by: Gaston Gonzalez <gascoar@gmail.com>
Link: https://lore.kernel.org/r/20210919215914.539805-4-gascoar@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>