ASoC: davinci: Kill BUG_ON() usage

commit befff4fb upstream

Don't use BUG_ON() for a non-critical sanity check on production
systems.  This patch replaces with a softer WARN_ON() and an error
path.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>