staging: vc04_services: use bcm2835 consequently

The naming bcm2708 is used only in the vendor kernel, so better
replace it with bcm2835 which is used in mainline in order
to avoid any confusion.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>