ASoC: wm9712: Cleanup printk usage

Use dev_err() instead of printk(KERN_ERR. This is common practice and makes
it easy to find out which device generated the message. While we are at it
also align the error messages with the other AC'97 drivers.

Also avoid printing two error messages when the reset fails.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>