ASoC: atmel: disable error interrupt

As once the error interrupt is triggered, it can not be cleared.
So, disable it.

No side effect found while testing on sama5d3xek and at91sam9x5ek
boards.

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>