staging: bcm2835-camera: Return early on errors

staging: bcm2835-camera: Return early on errors

Fix several instances where it is easier to return
early on error conditions than handle it as an else
clause. As requested by Mauro.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Acked-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>