video: convert drivers/video/* to use module_spi_driver()

This patch converts the drivers in drivers/video/* to use the
module_spi_driver() macro which makes the code smaller and a bit simpler.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Imre Deak <imre.deak@nokia.com>
Cc: Roger Quadros <roger.quadros@nokia.com>
Cc: Steve Sakoman <steve@sakoman.com>
Cc: Erik Gilling <konkers@android.com>
Cc: Gražvydas Ignotas <notasas@gmail.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>