linux-phytec-ti

ALSA: pcm: Unify snd_pcm_group initialization

There are multiple open codes that initialize the same object.
Create a common helper function instead.

Also, use kzalloc() to be safer at creating a group object, and move
the initialization out of the critical section.

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