ASoC: soc-pcm: return correct -ERRNO in failure path

Kernel test robot throws below error ->

sound/soc/soc-pcm.c:2523 dpcm_run_update_startup() error: uninitialized
symbol 'ret'.

Initializing ret = 0 and returning correct -ERRNO in failure path.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Link: https://lore.kernel.org/r/1610163901-5523-1-git-send-email-jrdr.linux@gmail.com


Signed-off-by: Mark Brown <broonie@kernel.org>