ARM: dts: Fix I2S1, I2S2 compatible for exynos4 SoCs

I2S1, I2S2 on Exynos4 SoC series have limited functionality compared
to I2S0, "samsung,s3c6410-i2s" compatible should be used for them.

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