ASoC PCM core deals the empty ioctl field now as default.
Let's kill the redundant lines.

Cc: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20191210145406.21419-3-tiwai@suse.deSigned-off-by: Mark Brown <broonie@kernel.org>