ASoC: Add snd_soc_of_put_dai_link_codecs() helper function

The code for dereferencing device nodes in the 'codecs' array is moved
to a separate function so we can avoid open coding that in drivers.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>