ASoC: imx-spdif: Fix crash on suspend

When registering a ASoC card the driver data of the parent device is set to
point to the card. This driver data is used in the
snd_soc_suspend()/resume() callbacks.

The imx-spdif driver overwrites the driver data with custom data which
causes snd_soc_suspend() to crash.  Since the custom driver is not used
anywhere simply deleting the line which sets the custom driver data fixes
the issue.

Fixes: 43ac9469

 ("ASoC: imx-spdif: add snd_soc_pm_ops for spdif machine driver")
Tested-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>