[media] exynos-gsc: change spamming try_fmt log message to debug

The driver try_fmt handler prints a message each time that the image
size has been changed due the maximum and minimum width and height.

Since user-space can try different format and sizes, this logs a lot
of unnecessary messages. Change the message log level to debug and
while being there, also add a new line to the message.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>