media: i2c: ov9640: add space before return for better clarity

Some returns were adjoined to unrelated code blocks. This patch adds
a space inbetween.

Signed-off-by: Petr Cvek <petrcvekcz@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>