ASoC: samsung: i2s: Define the parameters list for SAMSUNG_I2S_OPCLK

The SAMSUNG_I2S_OPCLK is not currently used by any card driver thus we can
safely change semantics of 'dir' argument of the I2S set_sysclk() callback.
Now an enumeration is exported instead of directly using register bit field
values.

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