ALSA: ASoC: Refactor DAPM event handler

The DAPM event callback code has many layers of indentation, taking it
over 80 columns. Refactor the code to give less indentation in order to
avoid checkpatch issues on further changes and exploding indentation.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>