Staging: vc04_services: bcm2835-camera: Fix spelling mistake

Fixes a spelling mistake in the comments.
Problem found using checkpatch.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>