media: i2c: ov7670: Put ep fwnode after use

The just parsed endpoint fwnode has to be put after use.
Currently this is done only in error handling path. Fix that by
putting node unconditionally after use.

Fixes: 01b84448 ("media: v4l2: i2c: ov7670: Implement OF mbus configuration")

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>