[media] soc-camera: remove redundant code

A hunk, removing this code has been lost between versions 6 and 7 of
patch "soc-camera: add V4L2-async support." The code is harmless, but
redundant.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>