ALSA: firewire: Drop superfluous ioctl PCM ops

All the PCM ioctl ops of ALSA FireWire drivers do nothing but calling
the default handler.

Now PCM core accepts NULL as the default ioctl ops(*), so let's drop
altogether.

(*) commit fc033cbf

 ("ALSA: pcm: Allow NULL ioctl ops")

Acked-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20191210061145.24641-6-tiwai@suse.de


Signed-off-by: Takashi Iwai <tiwai@suse.de>