ALSA: hda - Fix build error in hda_tegra.c

The "list" field has been omitted from struct azx, but its
initialization remained mistakenly in hda_tegra.c, which leads to a
compile error:
   sound/pci/hda/hda_tegra.c: In function 'hda_tegra_create':
   sound/pci/hda/hda_tegra.c:481:22: error: 'struct azx' has no member
named 'list'

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 9a34af4a3327 ('ALSA: hda - Move more PCI-controller-specific stuff from generic code')
Signed-off-by: Takashi Iwai <tiwai@suse.de>
ALSA: echoaudio: Remove unused variable

'chip' is not used in the function. Remove it.

Signed-off-by: Sachin Kamat <sachin.kamat@samsung.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
ALSA: mixart: Remove unused variable

'err' is not used in the function. Remove it.

Signed-off-by: Sachin Kamat <sachin.kamat@samsung.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>