[media] s5p-fimc: Convert to the device managed resources

The devm_* functions are used in the platform device probe() for data
that is freed on driver removal. The managed device layer takes care
of undoing actions taken in the probe callback() and freeing resources
on driver detach. This eliminates the need for manually releasing
resources and simplifies error handling.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>