staging: bcm2835-camera: Use designators to init V4L2 controls

The initializer lists for the V4L2 controls are hard to read.
So improve this by using designators.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/1584049059-6772-3-git-send-email-stefan.wahren@i2se.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>